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FOC Glossary

View: Glossary, Acronyms, Military Specifications for Connectors

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There are currently 3626 names in this directory
1-Part, AL-12xx Series
ÅngströmLink® non-curing gels. Also known as thixotropic gels, or greases, these are 1-part materials that flow when pressure is applied, and remain in place when the force is removed (like toothpaste). These materials are generally used to displace the air gap between two optical elements and do not form a permanent bond between the two elements; generally need other mechanical fastening to insure structural integrity of the joint. Joints interconnected in this way are easily unmade and remade.

10 Gigabit Ethernet
The IEEE has initiated work on the specification of 10 Gigabit Ethernet over optical fiber cabling. The standard is planned for completion in 2001 or early 2002, with specifications for multimode and singlemode fiber.

A Carrier
The non-wireline cellular company which operates in radio frequencies from 824 to 849 MHz.

A-Block Carrier
30-MHz personal-communications-services provider serving a major trading area in the frequency block of 1850 to 1865 MHz paired with 1930 to 1945 MHz.

A-stage
An early stage in the preparation of certain thermosetting resins, in which the material is still soluble in certain liquids, and fusible.

A.C. Resistance
The total resistance offered by a device in an alternating current circuit due to inductive and capacitive effects, as well as the direct current resistance.

Abhesive
A material which is adhesive resistant and applicable as a non-sticking surface coating; release agent.

Abrasion
Surface wear on the wires of a wire rope

Abrasion Resistance
A measure of ability of a wire, wire covering or material to resist surface wear or damage by mechanical means.

Absorption
That portion of fiber optic attenuation resulting of conversion of optical power to heat.

AC Alternating Current (AC)
Current in which the charge-flow periodically reverses.

AC Resistance
The total resistance offered by a device in an alternating current circuit due to inductive and capacitive effects, as well as the direct current resistance .

Accelerated Aging
A test in which voltage, temperature, etc., are increased above normal operating values to obtain observable deterioration in a relatively short period of time. The plotted results give expected service life under normal conditions.

Accelerated weathering
A set of laboratory conditions to simulate in a short time the effects of natural weathering. Most adhesives are generally not subjected to the conditions that are normally considered under weathering tests.

Acceleration Stress
Additional stress imposed on a wire rope due to increasing the velocity of the load

Accelerator
A chemical additive which hastens a chemical reaction under specific conditions.

Acceptance Angle
The half-angle of the cone within which all incident light is totally internally reflected by the fiber core. For graded index fibers, acceptance angle is a function of position on the entrance face of the core.

Acceptance Test
Made to demonstrate the degree of compliance with specified requirements.

Access Method
In a data processing system, any of the techniques available to end users for movement of data between main storage and an input/output device or channel. These techniques are most commonly a part of the operating system.

Accessories
Mechanical devices such as back-shells, cable clamps or strain reliefs which are attached to connectors to make up the total connector assembly.

Accordian
(1) A retractile cable with a series of equally-spaced transverse folds. (2) A connector contact with a Z shaped flat spring to permit high deflection without overstress.

Acetate (cellulose acetate)
A transparent film which is used for various reasons in tape backings; the primary characteristic is that of being more moisture resistant than cellophane.

Acetone
A very volatile and flammable solvent that is particularly useful for cleaning metal substrates.

Acrylic
A synthetic polymer with excellent aging characteristics that can be used as either a single component adhesive, coating or saturant, depending upon composition.

Activator
A chemical additive used to initiate the chemical reaction in a specific chemical mixture .

Active Current
In an alternating current, a component in phase with the voltage. The working component as distinguished from the idle or wattless component.

Active device
An active device is a device that requires electrical power. One type is those that convert signals between electrical and optical formats such as lasers, LEDs, and photodiodes. Active devices also can manipulate light, such as optical amplifiers and modulators.

Active optical cable (AOC)
A fiber optic cable that has been preterminated with an external electrical endface, thereby removing the termination process. The electrical endfaces can be manufactured with most module formats. The most common module formats are the SFP and HDMI interfaces, but DVI, VGA, SFP+, and QSFP+ interfaces also can be provided.

Active Pressure
In an AC circuit, the pressure which produces a current, as distinguished from the voltage impressed upon the circuit.

Active Tag
An RF identification transponder that requires batteries for operation.

Ad Hoc Cabling
Cabling scheme where different types of cabling components from different vendors are linked together to form a cabling system.

Adapter
A device that enables any or all of the following a) different sizes or types of plugs to mate with one another or to fit into a telecommunications outlet/connector; b) the rearrangement of leads; c) large cables with numerous wires to fan out into smalle

Adapter-Fiber
A mechanical media termination device designed to align and join fiber optic connectors. Often referred to as a coupling, bulkhead, or interconnect sleeve.

Add/drop multiplexer (ADM)
A mid-span electronic element that provides optoelectric/electro-optic conversion to add, drop, or multiplex photonic signals.

Addition polymerization
1) A chemical reaction in which simple molecules are linked together to form long chain molecules; 2) A chain reaction in which monomers with carbon-carbon double bonds are converted to polymers.

Adhere
To cause two surfaces to be held together by adhesion.

Adherend
A body which is held to another body by an adhesive.

Adhesion
The state in which two surfaces are held together by interfacial forces which may be chemical or mechanical in nature .

Adhesion (adhesive) failure
Rupture of an adhesive bond in which the separation appears visually to be at the adhesive/adherend interface.

Adhesion build-up
An increase in the peel adhesion value of a pressure-sensitive tape after it has been allowed to dwell on the applied surface.

Adhesion promoter
A substance used to improve bonding of the adhesive to the substrate. (Compare coupling agent and primer.) Discussion—The adhesion promoter may be added to an adhesive formulation or applied to the substrate.

Adhesion to backing
The bond produced by contact between a pressure-sensitive adhesive and the tape backing when one piece is applied to the back of another piece of the same tape.

Adhesion, mechanical
Adhesion between surfaces in which the adhesive holds the parts together by interlocking action.

Adhesion, specific
Adhesion between surfaces that are held together by valence forces of the same type as those which give rise to cohesion.

Adhesive
Substance for bonding, sticking or holding things together.

Adhesive Bonded
Cables bonded by adding an adhesive coating to the surface of the cable components, then joining and curing the adhesive to form a cable. See Bonded Cables.

Adhesive deposit
A pressure-sensitive adhesive which is pulled away from the tape and remains on the surface to which the tape was applied.

Adhesive dispersion
A two-phase system in which one phase is suspended in a liquid.

Adhesive failure
Type of failure characterized by pulling the adhesive loose from the substrate.

Adhesive joint
Location at which two adherends are held together with a layer of adhesive. (See also bond )

Adhesive Liner
Lining the melts and flows inside a sleeve filling any voids in between the substrate and the sleeve

Adhesive transfer
The transfer of adhesive from its normal position on the tape to the surface to which the tape was attached, either during unwind or removal.

Adhesive-joint failure
The locus of fracture occurring in an adhesively-bonded joint resulting in a loss of load-carrying capability.

Adhesive, Anaerobic
An adhesive which only cures when air is excluded.

Adhesive, Assembly
An adhesive that can be used for bonding parts together such as the manufacture of a boat, airplane, furniture, and the like.

Adhesive, Cold-setting
An adhesive that sets at temperature below 68°F (20°C).

Adhesive, Contact
An adhesive that is apparently dry to the touch and which will adhere to itself instantaneously upon contact; also called contact bond adhesive or dry bond adhesive.

Adhesive, Cyanoacrylate
Group of adhesives which show "instant" cure properties and bond to a wide variety of substrates. Cure is by contact with alkaline materials. Weakly alkaline materials, such as water, cause the cure to start.

Adhesive, Dispersion
A two phase system in which one phase is suspended in a liquid.

Adhesive, Foamed
An adhesive, the apparent density of which has been decreased substantially by the presence of numerous gaseous cells dispersed throughout its mass. Same as cellular adhesive.

Adhesive, Foamed – An adhesive, the apparent density of which has been decreased substantially by the presence of numerous gaseous cells dispersed throughout its mass. Same as cellular adhesive.
An adhesive, the apparent density of which has been decreased substantially by the presence of numerous gaseous cells dispersed throughout its mass. Same as cellular adhesive.

Adhesive, Heat activated
A dry adhesive film that is rendered tacky or fluid by application of heat or heat and pressure to the assembly.

Adhesive, Hot melt
An adhesive that is applied in a molten state and forms a bond on cooling to a solid state.

Adhesive, Hot-setting
An adhesive that requires a temperature at or above 100°C (212°F) to set.

Adhesive, Intermediate temperature setting
An adhesive that sets in the temperature range of 31°-99°C (87°-211°F).

Adhesive, Pressure sensitive
A viscoelastic material which in solvent-free form remains permanently tacky. Such a material will adhere instantaneously to most solid surfaces with the application of very slight pressure.

Adhesive, Room temperature setting
An adhesive that sets in the temperature range of 20°-30°C (68°-86°F).

Adhesive, Separate application
A term used to describe an adhesive consisting of two parts, one part being applied to one substrate and the other part to the other substrate and the two brought together to form a joint.

Adhesive, solvent
An adhesive having a volatile organic liquid as a vehicle.

Adhesive, solvent activated
A dry adhesive film that is rendered tacky just prior to use by application of a solvent.

Adjacent Conductor
Any conductor next to another conductor either in the same multi-conductor cable layer or in adjacent layers.

Administration
The method for labeling, identification, documentation and usage needed to implement moves, additions and changes of the telecommunications infrastructure.

Administration Point
A location at which communications circuits are administered; that is, rearranged or rerouted by means of cross connections, interconnection, or information outlets.

Administration Subsystem
The part of a premises distribution system that includes the distribution hardware components where you can add or rearrange circuits. These components include cross connects, interconnects, information outlets, and their associated patch cords and plugs. Also called "administration points". See also Cross Connect and Information Outlets (IO).

Admittance
The measure of the ease with which an alternating current flows in a circuit. The reciprocal of impedance.

Adsorption
The action of a body in condensing and holding gases and other materials at its surface.

Advanced Intelligent Networks (AIN)
Systems that allow a wireless user to make and receive phone calls while roaming in areas outside the user’s “home” network.

Advanced Mobile Phone Service (AMPS)
The US standard for analog cellular telephones.

AEIC
Association of Edison Illuminating Companies

Aeolian vibration
Wind-induced vibration, usually high frequency, which causes oscillation of cable.

Aerial
A type of installation in which the cable is connected to poles or towers by means of clamps or other attachment hardware.

Aerial Cable
A cable suspended in the air on poles or other overhead structure

Aging
The progressive change in the chemical and physical properties of a sealant or adhesive.

Aging Stability Test
The test used to determine the flexibility of a cable after temperature cycling.

Aging, Heat
Artificial "aging" of adhesive by exposing to elevated temperatures for long periods.

Air blown fiber (ABF)
An installation technique developed by British Telecom where micro ducts or “pipe cables” are installed, and then optical fibers or fiber bundles are blown into the cable with spans reaching 10,000 feet.

Air Core
A telephone outside plant cable construction for aerial and duct installation in which the insulated conductors in the cable core are surrounded by air.

Air Core Cable
A cable in which the interstices in the cable core are not filled with a moisture barrier.

Air handling plenum
A space within a building that is designed for the movement of environmental air, e.g., a space above a suspended ceiling or below an access floor.

Air polish
The first polish of a ferrule or termini after the fiber has been cleaved. The lapping film is passed over the connector endface in the air to polish the fiber stub just above the ferrule endface.

Air Spaced Coaxial Cable
One in which air is essentially the dielectric material. A spirally wound synthetic filament, beads, or braided filaments may be used to center the conductor.

Air-Handling Plenum
A designated area, closed or open, used for environmental air.

Airborne
Denotes applications peculiar to aircraft and missiles or other systems designed for operation primarily within the earth's atmosphere. (MIL-STD)

Aircraft Cables
Strands, cords and wire ropes made of special strength wire primarily for aircraft controls and miscellaneous uses of Aircraft Industry

Airtime
Time spent talking on a cellular phone. This is usually billed to the subscriber on a per-minute basis.

Alignment sleeve
An appliance for mating and holding two connector ferrules in alignment. Also known as a C-clip.

Aliphatic resin glue
Yellow glues which provide more grab for shorter clamp times, and offer better water resistance and heat resistance than traditional white glues.

All-dielectric
No metal elements.

All-dielectric self-supporting (ADSS)
A loose tube cable structure without any metallic elements.

All-optical network (AON)
A network that uses only optical components to produce, direct, condition, control, and connect optical signals.

All-Rubber Cable
A cable in which all interstices between conductors are filled with rubber compound.

Alligator Clip
A mechanical device shaped like alligator jaws used as a temporary connection on the sod of interconnections wire.

Alligatoring
Cracking of a surface into segments so that it resembles the hide of an alligator.

Allocation
The designation of a band of frequencies for a specific radio service or services. The Federal Communications Commission and the National Telecommunications and Information Administration are responsible for frequency allocations in the US.

Alloy
A mixture of two or more metals combined to achieve properties, such as a lower melting point or greater strength, that the individual metals do not possess.

Alphanumeric
A message on a digital output display containing letters, “alphas”, and numbers, “numerics”.

ALS
A type of cable consisting of insulated conductors enclosed in a continuous, closely fitting aluminum tube.

Alternate Lay
Lay of a wire rope in which the strands are alternately regular and lang lay

Alternate Position
Mechanical arrangement of keyways, inserts or grooves in a connector shell or insert that allows connectors of the same configuration to be used without the danger of interconnection to the wrong mating connector. Also called Keying.

Alternating Copolymer
A copolymer consisting of macromolecules comprising two species of monomeric units in alternating sequence. (IUPAC)

Alternating Copolymerization
A copolymerization in which an alternating copolymer is formed. (IUPAC)

Alternating Current (AC)
Electric current that continually reverses its direction. It is expressed in cycles per second (hertz or Hz).

Alternating Voltage
The voltage developed a cross a resistance or impedance through which alternating current is flowing.

Aluminum Conductor
An aluminum wire or group of wires not suitably insulated to carry electrical current.

Aluminum Oxide Film (ÅngströmLap ®)
When diamond film is not needed, like in many multimode applications, aluminum oxide is recommended. Some

Aluminum-Steel Conductor
A composite conductor made up of a combination of aluminum and steel wires.

Ambient
The atmospheric conditions surrounding a given item. Normally in terms of factors which influence or modify, such as temperature, humidity, etc.

Ambient Conditions
Temperature, humidity, sunlight, etc. which exist in the area surrounding the bond, normally room temperature, atmospheric pressure, daylight, etc.

Ambient Temperature
The temperature of the medium surrounding an object. Generally a lower temperature than the temperature at which the cable is operating.

American National Standards Institute (ANSI)
The official American standards body through which standards are published and various other standards committees are accredited.

American Society for Testing Materials (ASTM)
An organization that tests materials and attempts to set standards on various materials for industry.

American Wire Gauge (AWG)
A standard system for measuring wire gauge primarily used in the United States.

Amorphous
Non-crystalline polymer or non-crystalline areas in a polymer.

Ampacity
The maximum current an insulated wire or cable can safely carry without exceeding either the insulation or jacket material limitations. (Same as Current Carrying Capacity.)

Amperage
Amps/Amperes/Ampacity/Rated Amperage -measurement of the flow rate of electricity. If you think in terms of water through a hose, amperage would be a measure of water volume flowing through the hose.

Ampere
A measurement of electrical current or amount of electric charge per second in a circuit. Frequently shortened to Amp. Its symbol is the letter A but in formulas it is sometimes expressed as the letter I._

Ampere's Law
The magnetic intensity at any point near a current carrying conductor can be compute on the assumption that each infinitesimal length of the conductor produces at the point of an infinitesimal magnetic density. The resulting magnetic intensity at the point is the vector sum of the contributions of all the elements of the conductor.

Amplified spontaneous emission (ASE)
The ratio of the optical power at the center of the laser line width to the optical power at a given distance, as measured using an optical spectrum analyzer with a set resolution bandwidth.

Amplitude
Height of a waveform that represents signal strength.

Anaerobic
In adhesives, a bonding method that uses its own chemical reaction to complete the adhesion.

Anaerobic adhesive
An adhesive that is kept in the uncured state by oxygen, as in air, and that cures in the absence of oxygen when exposed to metal ions, especially copper or iron.

Analog
The traditional method of transmitting voice signals where the radio wave is based on electrical impulses which occur when speaking into the phone. Today most cellular companies transmit in analog signals, but digital signal output is increasing.__1)Representation of data by continuously variable quantities.__2)A continuously variable audio or video signal.

Analog Signal
A signal in which the intelligence is represented by continuously varying quantities.

Anechoic Chamber
A room which simulates a free-space environment by lining all surfaces, including the floor, with absorbing material to reduce reflections of sound or electromagnetic waves. A semi-anechoic chamber has absorbing materials on walls and ceiling. The floor is then reflective to create a ground-plane effect.

Angle of Advance
The angle between a line perpendicular to the axis of the cable and the axis of any one member or strand of the braid.

Angle of Incidence
The angle between an incident ray and the normal to a reflecting surface.

Angle of Refraction
Angle formed between a refracted ray and the normal to the surface. This angle lies in a common plane with the angle of incidence.

Angled physical contact (APC)
A ferrule endface at 8° that minimizes Fresnel reflections when in contact with another APC termination. APC polishes normally have a component reflectance value of 60-70 dB. They are most often used in analog, DWDM, and FTTx installations.

Angular misalignment
The fiber optic cores of a mated pair of connectors are held at an angle, either by mispolish, worn alignment sleeve, or contamination.

Aniline dye
Any of a large number of synthetic dyes derived from aniline, usually obtained from coal tar.

Anionic Polymerization
An ionic polymerization in which the kinetic-chain carriers are anions. (IUPAC)

Anneal
Relief of mechanical stress through heat and gradual cooling. Annealing copper renders it less brittle.

Anneal (Soften)
To subject to high heat with subsequent cooling. When annealing copper, the act of softening the metal by means of heat to render it less brittle.

Annealed Wire
Wire which after drawdown has been heated and slowly cooled to remove the effects of cold working.

Annealing
The process of heating to and holding at a suitable temperature and then cooling at a suitable rate, for such purposes as reducing hardness, improving machinability, facilitating cold working, producing a desired micro-structure or obtaining desired physical, mechanical or other properties.

Annular Conductor
A number of wires stranded in three reversed concentric layers around a core.

Annunciator
A signaling device, usually electrically operated, that gives an audible or visual signal (or both) when energized.

Anode
The electrode in a device that electrons flow out of to return to the circuit. In a battery or other source of direct current the anode is the negative terminal, but in a passive load it is the positive terminal._

Anodize
Formation of a protective insulating oxide layer on a metal by electrolytic action.

Anodizing
An electrolytic process for producing a protective or decorative film on certain metals chiefly aluminum and magnesium.

Anti-Ozonant
A substance which prevents or slows down material degradation due to ozone reaction.

Anti-Rotation Connector
A cylindrical connector design which provides keying or locking provisions to maintain positive orientation for accessory hardware.

Anvil
The part of the crimping die normally stationary, which positions and supports the contact during crimping. Sometimes called "Nest".

Apex offset
As measured by an interferometer, when the radius of curvature of a connector’s endface polish is distorted enough to cause the fiber optic to appear off center.

Appliance Wire & Cable
A classification covering insulated wire and cable for internal wiring of appliances and equipment.

Application
A system, with its associated transmission method which is supported by telecommunications cabling.

Application Layer
The uppermost layer (layer 7) of the open systems interconnection (OSI) model. This layer is concerned with support to the user application and is responsible for managing the communication between applications, e.g. Email, File transfer, etc.

Application-specific optical fiber (ASOF)
Fibers built for specific applications such as those doped with erbium for use in fiber amplifiers or the high numerical aperture fibers used for manufacturing filters and gratings.

Aramid Fibers
A class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications for ballistic rated body armor fabric and ballistic composites, in bicycle tires, and as an asbestos substitute. The name is derived from merging of “aromatic polyamide”. They are fibers in which the chain molecules are highly oriented along the fiber axis, so the strength of the chemical bond can be exploited.

Aramid Yarn
Strength elements that provide tensile strength, support, and additional protection of fiber bundles. It is commonly referred to as Kevlar (a DuPont trademark).

Arc
The discharge from the electrodes of a fusion splicer.

Arc Resistance
The time require for an arc to establish a conductive path in a material.

Architecture
In networks, it is how the components are connected to and operate with one another. The term “network architecture” focuses on how fiber optic system elements communicate including functional organization (services) and configuration (topology and communications). Network architectures are usually designed as to their protocols. B-PON, G-PON, EPON, GEPON, SONET, ATM, Ethernet, etc., are examples of network architectures.

Area of Conductor
The sized of a conductor cross section measured in circular mils, square inches, etc.

Area, Metallic
Sum of the cross-sectional areas of individual wires in a wire rope or strand

Armor
Protective covering, usually metal, used underneath plastic jackets to provide additional environmental protection in harsh environments.

Armored cable
Cable with metallic sheathing or rods placed under or between cable jackets to prevent rodents from damaging the internal cable elements.

Armored Rope
Rope with individual strands spirally wrapped with flat steel wire

Array connector
Typically, connectors with multiple fibers in a small form factor housing, i.e., MPO, MTP, MT-RJ.

Arrayed waveguide grating (AWG)
A device that allows multiple wavelengths to be combined and separated in a DWDM system.

As-builts
Drawings that provide accurate depictions of cable running lines, pedestal locations, electronic sites, manholes, marker posts, etc., to aid with the management of cable assets and allow the facilities to be located, protected, maintained, and modified.

AskFOC
Technical resource area to receive answers on fiber optics, connectors, cable assembly, adhesives, lapping film, polymers and specialty products. Can be found at http://focenter.com/askfoc/

Asphalt
Naturally occurring mineral pitch or bitumen.

Assembly
A group of materials or parts, including the adhesive, which has been placed together for bonding or which has been bonded together.

Assembly Adhesive
An adhesive that can be used for bonding parts together, such as in the manufacture of a boat, airplane, furniture, and the like. Discussion—The term assembly adhesive is commonly used in the wood industry to distinguish such adhesives (formerly called joint glues) from those used in making plywood (sometimes called veneer glues). It is applied to adhesives used in fabricating finished structures or goods, or subassemblies thereof, as differentiated from adhesives used in the production of sheet materials for sale as such, for example, plywood or laminates.

Assembly Time
Also called Open Time. The time period from the application to adhesive until the final application of pressure. This term includes both Closed and Open Assembly Times.

Asymmetric digital subscriber line (ADSL)
A high-speed transmission technology that uses existing copper wires and involved electronic equipment to send digital signals from the telephone company central office to the subscriber’s premises. It sends more information one way than the other, hence it is “asymmetric.”

Asynchronous
Two or more signals sourced from independent clocks, therefore having different frequency and phase relations.

Asynchronous Data Transfer
A method of data transfer in which each alphabetic or numeric character (represented by 7 or 8 bits) is preceded by 'start' and 'stop' bits to delineate the 7/8 bit pattern from the ideal pattern which otherwise occupies the (digital) transmission medium.

Asynchronous Transmission
A data transmission technique controlled by start and stop bits at each end of a character and characterized by an undetermined time interval between characters.

Atactic macromolecule
A regular macromolecule in which the configurational (base) units are not all identical. (IUPAC)

Atactic polymer
A substance composed of atactic macromolecules. (IUPAC)

Attenuation
The loss of optical power, whether caused intrinsically (absorption, scattering, microbends, etc.), or extrinsically by components (connectors, splices, splitters, etc). Expressed as dB or dB/km (with fiber).

Attenuation Coefficient
The reduction in optical power as it passes along a fiber, usually expressed in decibels (dB).

Attenuation Stability
The change in attenuation of a coaxial cable after being subjected to specified temperature cycles and mechanical deformations.

Attenuation to Crosstalk Ratio (ACR)
The difference between attenuation and crosstalk, measured in dB, at a given frequency. Important characteristic in networking transmission to assure that signal sent down a twisted pair is stronger at the receiving end, after being attenuated, than are a

Attenuator
A device that reduces signal power in a fiber optic link by inducing loss.

Audio Frequency
The range of frequencies audible to the human ear. Usually 2- - 20,000 Hz.

Austenitic Types
Stainless steels that have high ductility, low yield stress and relatively high ultimate tensile strength, when compared to typical carbon steel. Added alloys (such as Nickel and Chrome) help increase corrosion resistance, among other properties

Authentication
The process used by the wireless carriers to verify the identity of a mobile station.

Automatic protection switching (APS)
Utilizing optical monitoring equipment, a network can be automatically switched over to a secondary network when the original network experiences a higher than normal loss or becomes inoperable.

Automatic test equipment (ATE)
Test equipment that is computer programmed to perform measurements on a device without changing the test setup.

Automatic Vehicle Identification (AVI)
AVI is the automatic identification of vehicles through the use of readers installed in toll booths or gates and RF transponders attached to or stored inside vehicles.

Automatic Vehicle Location (AVL)
A feature AVI that allows users to immediately locate commercial vehicles and fleets to reduce off-time and vehicle misuse. See Radiomobile division for more information on AVL.

AUTOTEST
A series of tests performed by a LAN Cable Tester activated by the AUTOTEST key. The content of a test series and the test limits are predefined by the selection of a Standard (e.g. Category 6), or a cable manufacturer’s test suite, or may be constructed by the test unit’s user.

Avalanche photodiode (APD)
A photodiode that takes advantage of avalanche multiplication of photocurrent to convert one photon to multiple electrons.

AVD Circuits
Alternate voice/data circuits

Average power
The average over time of a modulated signal.

AWG Equivalent
The American Wire Gauge round-conductor number that is used to designate a flat conductor with an equal cross-sectional area.

Axial Displacement
The incremental difference between an initial position and a final position resulting from a force applied along the axis of a component.

Axial ray
A ray passing through the axis of the optical waveguide without any internal reflection.

B & S Gauge
Standard for Brown & Sharpe Gauge. The wire diameter standard is same as AWG.

B Carrier
The wireline cellular carrier, usually the local telephone company, which operates on the frequencies of 869 to 894 MHz.

B-Block Carrier
A 30-MHz personal-communications services carrier serving a major trading area in the 1870-to-1885 MHz frequency range paired with the 1954-to-1965-MHz range.

B-stage
An intermediate stage in the reaction of certain thermosetting resins in which the material softens when heated and swells when in contact with certain liquids, but may not entirely fuse or dissolve. The resin in an uncured thermosetting adhesive is usually in this stage.

Back Mounted (rear mounting)
When a connector is mounted from the inside of a panel or box with its mounting flange inside the equipment.

BACK REFLECTION
Light reflected from the cleaved or polished end of a fiber caused by the difference of the refractive indices of air andglass. Back Reflectance is typically 4% of the incident light. It is expressed in dB relative to incident power.

Back Reflection (Fiber Optic)
A measure of the percentage of power reflected back by a discontinuity in a fiber optic line. It is expressed in dB.

Back reflection, optical return loss
Light reflected from the cleaved or polished end of a fiber caused by the difference of refractive indices of air and glass. Typically 4% of the incident light. Expressed in dB relative to incident power.

Back-Mounted (Rear Mounting)
A connector mounted from the inside of a panel or box with its mounting flange inside the equipment.

Back-Stay
Used to support a boom or mast: or that section of a main cable, as on a suspension bridge, cable-way, etc., leading from the tower to the anchorage

Backbone
The cabling used to connect entrance facilities, crossconnects, telecommunications closets, and equipment rooms. The backbone may consist of either interbuilding and/or intrabuilding cabling.

Backend Network
A local area network that connects computers’ input/output systems to shared storage devices. They may also be used for high data rate inter-computer data transfer.

Backplane Panels
An interconnection panel into which PC cards or other panels can be plugged. These panels come in a variety of designs ranging from a PC motherboard to individual connectors mounted in a metal frame. Panels lend themselves to automated wiring.

Backreflection
The loosely-used term covers optical return loss (ORL) for spans, reflectance for components, and Fresnel reflectance.

Backscatter coefficient
The ratio of the optical pulse power (not energy) at the OTDR output to the backscatter power at the near end of the fiber (z=0). This ratio is inversely proportional to the pulse width, because the optical pulse power is independent. It is expressed in dB.

Backscattering
The scattering of light in a fiber back toward the source, used to make OTDR measurements. Bandwidth: The range of signal frequencies or bit rate within which a fiber optic component, link or network will operate.

Backshell
Any device added to the rear (wiring side) of a connector to enhance the connector's operational characteristics.

Backshell Mold
A mold used to form a covering over the backshell of a connector after it is connected to a cable.

Bag molding
A method of molding or bonding involving the application of fluid pressure, usually by means of air, steam, water, or vacuum, to a flexible cover which, sometimes in conjunction with the rigid die, completely encloses the material to be bonded.

Bakelite
A polymer produced by the condensation of phenol and formaldehyde.

Balance
Balance is the ratio of the differential signal output at either end of any pair to a common mode

Balanced Circuit
A circuit so arranged that the impressed voltages on each conductor of the pair are equal in magnitude but opposite in polarity with respect to ground.

Balanced Line
A cable having two identical conductors which carry voltages opposite in polarity and equal in magnitude with respect to ground.

Balanced Twisted Pair Cable
A cable consisting of one or more metallic symmetrical cable elements (twisted pairs or quads).

Balun
A device for matching impedance between a balanced to unbalanced line, usually twisted-pair and coaxial cable.

Band
A range of optical spectrum allocated based on optical amplifiers. Six bands are specified by the ITU: O (original), E (enhanced), S (short), C (conventional), L (long), and U (ultra). These cover the optical spectrum from 1260 nm to 1675 nm.

Band Marking
A continuous circumferential band applied to a conductor at regular intervals for identification.

Banded Cable
Two or more cables banded together by stainless steel strapping.

Bandmarking
A circumferential color band applied to an insulated conductor at regular intervals for identification.

Bandwidth
A characterization of the information caring capacity of a multimode optical fiber. It is expressed in terms of frequency and is often normalized to a unit length (e.g., MHz-km). The frequency range over which the connector or device can operate without degradation of performance. Also the information carrying capacity of digital systems.

Bank Wire
An insulated wire used for the interconnection of selector switches in automatic telephone exchanges.

Bare Conductor
A conductor having no covering. A conductor with no coating or cladding on the copper.

Barrel Chamfer
Bevel at the end of the conductor barrel for easier entry of the conductor. (MIL-STD)

Barrel Conductor
The section of the terminal, splice or contact that accommodates the stripped conductor. (MIL-STD)

Barrel Insulation
The section of the terminal, splice or contact that accommodates the conductor insulation. (MIL-STD)

Barrel-Packed
Method of coiling into a fiber drum for shipment.

Barrier
A partition of electrically non conductive material which increases the electrical path between adjacent electrical circuits or an electrical circuit from ground.

Barrier Seal
The seal preventing the passage of moisture or gases through the insulator and the gap between insulator and center conductor or outer conductor of a connector or adapter.

Base Material
The metal from which the connector, contact, or other piece part accessory is made and on which one or more metals or coatings may be deposited.

Base Meta
The metal from which the connector, contact or other metal accessory is made and on which one or more metals or coatings may be deposited.

Base Metal
Metal from which the connector components are made and on which one or more metals or coatings may be deposited. Also called Basic Metal.

Base Station
The fixed transmitter/receiver device that a mobile radio transceiver establishes a communication link with in order to gain access to the public-switched telephone network.

Baseband
A network in which the entire bandwidth of the transmission medium is used as a single digital signal. Unlike broadband, no modulation techniques are used.

Baseband Signaling
Transmission of a digital or analog signal at its original frequencies, i.e., a signal in its original form, not changed by modulation.

Baseband Video
An application that defines transmission characteristics up to 862 MHz.

Basic Conductor Load
The limiting conductor-load per unit length assumed for the purposes of design.

Basic Link
A testing configuration that appeared in older editions of the ANSI/TIA/EIA-568-A Standard. It has been replaced by Permanent Link test configuration in the 568-B Standard that replaced 568-A. See PERMANENT LINK.

Basic Rate Interface (BRI)
The simplest form of network access available on the ISDN (integrated services digital network). The BRI comprises 2B + D channels for carriage of signaling and user information.

Basic Trading Area (BTA)
A service area designed by Rand McNally and adopted by the Federal Communications Commission to promote the rapid deployment and ubiquitous coverage of personal communications services. BTA’s generally cover a city and its surrounding area. They are a component of a major trading area. There are 493 BTA’s in the US.

Basis Metal
Metal from which the connector components are made and on which one or more metals or coatings may be deposited.

Batch
The manufactured unit or blend of two or more units of the same formulation and processing.

Battery Cable
A single conductor cable, insulated or uninsulated, used for carrying current from batteries to the point power is needed.

Baud
The most basic unit of data transmission speed, one baud represents one signal state change per second. It is often confused with bits per second (bps) because they were at one time very similar. By using current data compression and modulation techniques, many times the baud rate in bits per second can be achieved.

Bayonet
A locking prong and slot interconnect device. The mechanical latching mechanism for the ST-type connector.

Bayonet Coupling
A quick coupling device for plug and receptacle connectors, accomplished by rotation of a cam operating device designed to bring the connector halves together.

Bayonet fiber-optic connector (BFOC)
The formal name for the ST connector, a specific slotted twistlock connector with 2.5-mm ferrule.

BCH Code
Bose-Chaudhuri-Hocquenghem Code

Bead-rod model
A model simulating the hydrodynamic properties of a chain macromolecule consisting of a sequence of beads, each of which offers hydrodynamic resistance to the flow of the surrounding medium and is connected to the next bead by a rigid rod which does not. The mutual orientation of the rods is random. (IUPAC)

Bead-spring model
A model simulating the hydrodynamic properties of a chain macromolecule consisting of a sequence of beads, each of which offers hydrodynamic resistance to the flow of the surrounding medium and is connected to the next bead by a spring which does not contribute to the frictional interaction but which is responsible for the elastic and deformational properties of the chain. The mutual orientation of the springs is random. (IUPAC)

Beaded Coax
Coaxial cable with a dielectric consisting of beads made of various materials.

Beam splitter
A passive device that uses optical lenses with reflective coatings to control the split ratio and divide an optical beam into two or more beams.

Bedding
A layer of material applied to a cable immediately below the armoring.

Bell Wire
Insulated copper wire for making doorbell and thermostat connections in homes.

Belled Mouth (Bellmouth)
The flared or wide entrance of a terminal splice or contact barrel to permit easier insertion of the conductor.

Bellmouth
The raised portion at the front and/or back of the wire barrel crimp that provides a gradual entrance and exit for the wire strands without causing damage.

Belt
Number of layers of insulation on a conductor, or number of layers of jacket on a cable.

Belted-Type Cable
Multiple conductor cable having a layer of insulation over the assembled insulated conductors.

Bend insensitive fiber (BIF)
Single-mode fibers that have been modified to demonstrate reduced bend radius characteristics without attenuation changes. Specified in the ITU-T G.657 standard.

Bend loss
Increased attenuation due to macrobends (curvature of fiber) or microbends (small distortions in the fiber) coupling light energy from the fiber core to the cladding.

Bend Radius
Radius of curvature that a fiber optic or metallic cable can bend without any adverse effects.

Bending loss
Loss in fiber caused by stress on the fiber bent around a restrictive radius. Bit-error rate (BER): The fraction of data bits transmitted that are received in error.

Bending Stress
Stress imposed on wires of a wire rope by bending

Beryllium Copper
A relatively expensive contact material with properties superior to brass or phosphor bronze. It is used for contact applications requiring repeated extraction and reinsertion because of its resistance to fatigue at high operating temperatures.

Beta Format
A video recording format generally used in home recording.

Bias current
The steady current applied to a laser diode to overcome its threshold current.

Biconic
A phenolic-bodied, threaded, spring-loaded, non-keyed connector with a cone-shaped alignment area.

Biconical Antenna
A broadband dipole antenna used to measure and produce electric fields from approximately 30 MHz to 300 MHz.

Bidirectional (Bidi)
Operating in both directions over a single fiber.

Bidirectional transceiver
A device that sends information in one direction and receives information from the opposite direction.

Bifilar
A winding made non-inductive by winding together (as one wire) two wires carrying current in opposite directions.

Bifurcated Contact
A flat spring contact with lengthwise slotting which is used in a printed circuit edge connector. (MIL-STD)

Billion Conductor Feet (BCF)
A quantity derived by multiplying the number of conductors in a cable by the amount of cable. Usually used to indicate plant capacity or an annual requirement.

Bilog Antenna
A combination of biconical and log periodic antenna with an automatic crossover network with a frequency range from 26MHz to 2 GHz.

Bimetallic Wire
A wire formed of two different metals joined together (not alloyed). It can include wire with a steel core clad wire, or plated or coated wire.

Binder
Spirally served tape or thread used for holding assembled cable components in place.

Binder (adhesives)
In adhesive compounds , a component of an adhesive composition that is primarily responsible for its mechanical strength and adhesion.

Binding Post
A device for clamping or holding electrical conductors in a rigid position.

Bir-Directional
Measuring the DUT from both ends, must use Dual MTJ.

Birefringence
The refraction of light in two slightly different directions to form two rays; the phenomenon can be used to locate stress in a transparent material.

BIT
Binary Digit. The smallest unit of data (and most basic) for data communications. It can have a value of a one (mark) or a zero (space).

Bit Error Rate (BER)
A measure of quality of a digital transmission line, either quoted as a percentage, or more usually as a ratio, typically 1 error in 10E8 or 10E9 bits carried. The lower the number or errors, the better quality the line.

Bit error rate tester (BERT)
Test equipment that measures the bit error rate (BER) of digital transmission systems.

Bit rate
A unit of measure for digital transmission speeds expressed in bit per second (b/s).

Blister
An elevation of the surface of a substrate, somewhat resembling in shape a blister on the human skin; its boundaries may be indefinitely outlined and it may have burst and become flattened.

BLOCK
1) A group of transmitted data, typically framed with control characters and having a fixed size, such as 256, 512, 4096, etc; 2) A portion of a macromolecule, comprising many constitutional units, that has at least one feature which is not present in the adjacent portions. (IUPAC)

Block copolymer
A copolymer that is a block polymer. In a block copolymer, adjacent blocks are constitutionally different, i.e., each of these blocks comprises constitutional units derived from different characteristic species of monomer or with different composition or sequence distribution of constitutional units. (IUPAC)

Block macromolecule
A macromolecule which is composed of blocks in linear sequence. (IUPAC)

Block polymer
A substance composed of block macromolecules. (IUPAC)

Blocked curing-agent
A curing or hardening agent temporarily rendered unreactive, which can be reactivated as desired by physical or chemical means.

Blocking
Creating a physical barrier to keep moisture-repellent gel in loose tube cables from migrating or flowing out of the buffer tubes into splice trays; An undesired adhesion between touching layers of material such as occurs under moderate pressure during storage or use.

Blog
Short form for weblog

Blown Jacket
Outer cable covering applied by controlled inflation of the cured jacket tube then pulling the cable through it.

Blueprint
A detailed plan or design._

Bluetooth
A technology that enables data connections between electronic devices such as desktop computers, wireless phones, electronic organizers and printers in the 2.4 GHz range.

BNC Connector
Bayonet Siel-Concelmann Connector

Body
Main, or largest, portion of a connector to which other portions are attached.

Bond
Interface of the adhesive and the substrate; The attachment between an adhesive and an adherend; To join adherends by means of an adhesive.

Bond face
The part or surface of a building component which serves as a substrate for an adhesive.

Bond Strength
Amount of adhesion between bonded surfaces; The unit load applied in tension, compression, flexure, peel, impact, cleavage, or shear, that is required to break an adhesive assembly with failure occurring in or near the plane of the bond.

Bondable Wire
An insulated wire treated to facilitate adherence to materials such as potting compounds. Also, magnet wires used in making coils when bonding the turns together is desired .

Bonded Assembly
A connector assembly in which the components are bonded together using an electrically appropriate adhesive in a sandwich structure to provide sealing against moisture.

Bonded Cable
Cable consisting of pre-insulated conductors or multi-conductor components laid-in parallel and bonded into a flat cable.

Bonded Construction
An insulation construction in which the glass braid and nylon jacket are bonded together.

Bonded Flat Cable
Flat cable consisting of individually insulated conductors lying parallel and bonded together: application in electronics, telecommunications or computers.

Bonding
The permanent joining of metallic parts to form an electrically conductive path that will assure electrical continuity and the capacity to conduct safely any current likely to be imposed on it.

Bonding Conductor
An insulated or uninsulated conductor forming part of the cable assembly which is used for the purpose of connecting non-current carrying parts of electrical equipment to a system grounding conductor.

Bondline
The layer of adhesive which attaches two adherends.

Booster
A device inserted into a line or cable to increase the voltage.

Boot
(1) Protective covering over a cable, wire or connector in addition to the normal jacketing or insulation. (2) A form placed around wire termination of a multiple-contact connector to contain the liquid potting compound before it hardens.

Borate
To add Borax to a starch adhesive to improve adhesive tack and viscosity.

BORSCHT Functions
Battery Feed, Over Voltage (protection from lightning and accidental power line contact), Ringing, Supervision, Codec (A/D interconversion, also low pass audio filtering), Hybrid (directional coupler, 2-wire to 4-wire inter-conversation), Testing

Braid
1)A fibrous or metallic group of filaments interwoven in cylindrical form to form a covering over one or more wires. __2)Flexible conductor made of a woven or braided assembly of fine wires. (MIL-STD)__3)A woven protective outer covering over a conductor or cable. It may be composed of any filamentary materials such as cotton, glass, nylon, tinned copper, silver, or asbestos fibers.

Braid Angle
1)The smaller of the two angles formed by the shielding strand and the axis of the cable being shielded.__2)The angle between the axis of the cable and the axis of any one member or strand of the braid. (Also known as the angle of advance)

Braid Carrier
A spool or bobbin on a braider that holds one group of strands or filaments consisting of a specific number of ends. The carrier revolves during braiding operations.

Braid Coverage
A calculated percentage which defines the completeness with which a braid or shield covers the surface of the underlying component.

Braid Ends
The number of strainds used to make up one carrier. The strands are wound side by side on the carrier bobboin and lie parallet in the finished braid.

Braiding Machine
Machine used to apply braids to wire and cable and to produce braided sleeving and braids for tying or lacing purposes. Braiding machines are identified by the number of carriers.

Brake Wire
Wire used in mobile-home, travel and truck trailers to supply current to the electrical braking system.

Branched polymer
Polymer having smaller chains attached to the polymer backbone.

Brass
A low cost connector material which is an excellent electric conductor. Brass reaches its yield point at low deflection force, thus it deforms easily and fatigues slowly. Used in connector bodies and male contacts.

Brazing
The joining of ends of two wires, rods or groups of wires with a nonferrous filler metal at temperatures above 800oF (427oC).

Breakaway Torque
Measure of force needed to initiate movement of an unseated fastener in a loosening direction.

Breakdown (Puncture)
A disruptive discharge through insulation.

Breakdown of Insulation
Failure of an insulation resulting in a flow of current through the insulation. It may be caused by the application of too high voltage or by defects or decay.

Breakdown Voltage
The voltage at which the insulation between two conductors will break down or arc over.

Breaking Strength (aggregate wire)
The sum of the breaking strength in tension of all the wires of a wire rope when the wires are tested individually

Breaking Strength (wire rope)
The measured load required to break a wire rope in tension

Breakout
1)The point at which a conductor or group of conductors is separated from a multiconductor cable to complete circuits at various points along the main cable.__2)A breakout is the common name given to the exit point of a conductor or number of conductors from a cable of which they are a part. This point is usually harnessed or sealed with some synthetic rubber compound.

Breakout Cable
Multi-fiber cable constructed in the tight buffered design with individually jacketed fibers. Designed for ease of connectorization and rugged applications for intra- or inter-building requirements.

Breakout kit
A kit that provides a breakout cable structure for non-breakout structures (with one fiber per tube).

BRIDGE
In the LAN arena, it is a device used to connect two physically separate networks.

Bridged Tap
The multiple appearances of the same cable pair at several distribution points.

Bridging
A high impedance parallel connection.

Bridle Sling
A two-part wire rope sling attached to a single part line. The legs of the sling are spread to divide and equalize the load

Bright Rope
Wire rope made of wires that are not coated with zinc, tin, or any other protective metal

Brillouin Scattering
In stimulated Brillouin backscattering (SBS), the laser signal creates periodic regions of altered refractive index; that is, a periodic grating that travels as an acoustic wave away from the signal. This effect can result in a noisy and unstable forward-propagating signal, since much of the optical energy is backscattered.

British Standard Wire Gauge
A modification of the Birmingham Wire Gauge and the legal standard of Great Britain for all wires. Also known as Standard Wire Gauge (SWG), New British Standard (NBS), English Legal Standard and Imperial Wire Guide.

Brittle Temperature
The temperature below which a material becomes brittle, often measured by a cold impact test.

Broadband
A transmission facility that has a bandwidth (capacity) capable of carrying numerous voice, video and data channels simultaneously. Each channel operates on a different frequency. Cable TV is a broadband transmission.

Broadband PCS
Personal-communications-services systems offered in 30-MHz blocks at 1.9-GHz; voice-capable versus narrowband personal communications services, which is paging oriented.

Broadband PON (B-PON)
The first FTTx standard issued as ITU-T G.983, the B-PON standard was designed for the bidirectional transmission of ATM cells over G.652 single-mode fiber at a distance of 20 kilometers using wavelength independent couplers (splitters) with split rates of up to 1:32. Originally defined by the FSAN S652 document.

Broadcast
To send a message to two or more receiving devices at the same time.

Broadcast Transmission
Message transmission which may be read by a large number of destinations rather than just one. Satellite is an example.

Bronze Ropes
Wire rope made of bronze wires

BROUTER
A combination bridge and router, performing the functions of both in a single device.

Bubble splice
An air bubble in a splice that can cause high loss.

Buffer
A protective coating over an optical fiber. A soft material extruded tightly over the fiber coating, mechanically isolates individual fiber.

Buffer coating
A protective material with no optical function that covers and protects a fiber. A secondary plastic coating adhered around the coating of the optical fiber to provide additional protection against damage. Normally 250 or 900 microns.

Buffer tube
Part of a loose tube cable structure, buffer tubes accommodate 250-micron coated fibers in a loose configuration. The buffer tubes can be filled with gel, powder, or tapes to resist moisture intrusion.

Buffing Stripper
A motorized device for removing flat cable insulation by means of buffing wheels that melt the insulation and brush it away from the conductors. Also called Abrasion Stripper.

Building Backbone Cable
A cable that connects the building distributor to a floor distributor. Building backbone cables may also connect floor distributors in the same building.

Building Distributor
A distributor in which the building backbone cable(s) terminate(s) and at which connections to the campus backbone cable(s) may be made.

Building Entrance Area
A space in which the joining of inter- or intra-building telecommunications backbone facilities takes place. An entrance room may also serve as an equipment room.

Building Entrance Facility
A facility that provides all necessary mechanical and electrical services, that complies with all relevant regulations, for the entry of telecommunications cables into a building.

Building local exchange carrier (BLEC)
A network service provider that contracts with real estate, property owners, and building managers to provide broadband services within multiple tenant units or multiple dwelling units.

Building Wire
Insulated wires used in building for light and power, 600 volts or less, usually not exposed to outdoor environment.

Bulge splice
Slight overfeed results in bulging at the splice point. Bulging is not always lossy. Splice strength requires a solid fusion joint; monitor splice strength if you are reducing feed to eliminate bulging. Also known as a fat splice.

Bulk adherend
As related to interphase, the adherend, unaltered by the adhesive.

Bulk adhesive
As related to interphase, the adhesive, unaltered by the adherend.

Bulk compounds
Any sealant or caulk that has no defined shape and is stored in a container.

Bulkhead
A term used to define a mounting style of connectors. Bulkhead connectors are designed to be inserted into a panel cutout from the rear (component side) or front side of the panel.

Bunch Strand
Conductors twisted together with the same lay and direction without regard to geometric pattern.

Bunch Stranded Conductor
All strands having a random position within the conductor. No distinct layers are formed.

Bunched Stranding
A group of strands twisted together in a random manner and the same direction without regard to geometric arrangement of specific strands.

Buncher
A machine that twists wires together in random arrangement.

Bundle
Several individual fibers contain within a single jacket or buffer tube. Also a group of buffered fibers distinguished in some fashion from another group in the same cable core.

Bundled Cable
An assembly or two or more cables continuously bound together to form a single unit.

Buried
Cable placed by trenching, direct burial, plowing, boring, or installation into underground ducts.

Buried Cable
A cable installed directly in the earth without use of underground round conduit. Also called Direct Burial Cable.

Buried Distribution and Service Wires
Telephone wires which are designed to provide buried service extensions from distribution cables to the subscriber's protector.

Bursting strength
The ability of a tape to resist damage when force is evenly applied perpendicularly to the surface of the tape.

BUS
Wire used to connect two terminals insode of an electrical unit. Consists of a common transmission path with a number of nodes attached to it. Sometimes referred to as linear network topology; An electrical connection tying two or more points together. A bus can be serial or parallel and can carry both dynamic signals or DC voltage.

BUS Interface Unit (BUI)
The data-circuit terminating equipment which provides access to a LAN. It may also provide packet assembly/disassembly functions. May be an add-on card or a separate box.

BUS Network
A topology based on all communicating devices being attached to a common medium. Various access methods are used including CSMA/CD and Token Passing. Typically bus networks carry data in the millions of bits per second data rate.

Bus Topology
A local area network (LAN) topology in which endpoints connect to a single wire or fiber, or set of wires or fibers, at any point. The Ethernet LAN is one example.

BusBar Wire
Uninsulated tinned copper wire used as a common lead.

Bushing
A mechanical device used as a lining for an opening to prevent abrasion to wire and cable.

Business PCS
A communication system that adds wireless capability to an in-building or campus communications network. Also known as Wireless PBX or Enterprise PCS.

Busing
The joining of two or more circuits. (MIL-STD)

Butt
Joining of two conductors end-to-end, with no overlap and with the axes in line.

Butt closure
Closure with cable ports located at one end of the closure.

Butt Splice
A splice where two wires from opposite ends butt against each other, or against a stop, in the center of a splice.

Butt Wrap
Tape wrapped around an object or conductor in an edge-to-edge condition.

Butted Contact
The contact achieved when two conductors come together end-to-end, but do not overlap, with their axis in line.

Butting Dies
Crimping dies so designed that the nest and indentor touch at the end of the crimping cycle. Also called "Bottoming Dies" (MIL-STD)

Button Conveyor Rope
Wire ropes to which buttons or discs are attached at regular intervals to move material in a trough

Butyl Rubber
A synthetic rubber with good insulating properties.

Buy American Act
Federal legislation governing the requirements for domestically manufactured products used in federally funded procurement contracts

Bypass switch
A high-speed switch that transfers an optical signal to an alternate fiber.

BYTE
A binary string operated as a unit. The byte is usually shorter than a computer word and often is used to represent a character. Byte is used colloquially to refer to eight bits or binary digits.

C Format
A video recording format commonly used in commercial recording.

C Symbol
Designated for: capacitance, bias supply and centigrade.

C-band
The C-band is the “conventional” DWDM transmission band, occupying the 1530 to 1565 nm wavelength range, as specified by the ITU-T G.692. Most EDFAs operate in the C-band.

C-Block Area
A 30-MHz personal-communications-services carrier serving a basic trading area in the 1895-to-1910-MHz range paired with 1975 to 1990 MHz.

C-stage
The final stage in the reaction of certain thermosetting resins in which the material is relatively insoluble and infusible. Certain thermosetting resins in a fully cured adhesive layer are in this stage.

Cabinet
A container that may enclose connection devices, terminations, and equipment.

Cable
1)Either a stranded conductor with or without insulation and other coverings (single-conductor cable), or a combination of conductors insulated from one another (multiple-conductor cable).__2)A group of individually insulated conductors in twisted or parallel configuration under a common sheath.__3) One or more conductors within a protective sheath. See also coaxial cable, twisted pairs cable

Cable Bend Radius
The radius that a fiber can be bent before risking increased attenuation or fiber breaks.

Cable Clamp
A device used to give mechanical support to the wire bundle or cable at the rear of a plug or receptacle; A mechanical clamp attached to the cable side of the connector to support the cable or wire bundle, provide strain relief and absorb vibration and shock otherwise transmitted by the cable to the contact/wire connection. (MIL-STD)

Cable Clamp Adapter
A mechanical adapter that attaches to the rear of a plug or receptacle to allow the attachment of a cable clamp.

Cable Conductor
The portion of an insulated cable lying under the protective covering.

Cable Core
The portion of an insulated cable under the protective covering or coverings.

Cable Core Binder
A wrapping of tapes or cords around the conductors of a multiple-conductor cable used to hold them together.

Cable Fill
The ratio of cable installed into a conduit/trunking against the theoretical maximum capacity of the conduit/trunking.

Cable Filler
The material used in multiple-conductor cables to occupy the interstices in a cable to make the finished cable round.

Cable Harness
A string of cables and/or wires which transmit informational signals or operating currents (energy). The cables are bound together by clamps, cable ties, cable lacing, sleeves, electrical tape, conduit, a weave of extruded string, or a combination thereof.

Cable jacket
The protective outer covering of wire or optical cable. Common materials include polyethylene (PE), polyurethane (PU), polyvinyl chloride (PVC) and Teflon (plenum).

Cable Plant, Fiber Optic
The combination of fiber optic cable sections, connectors and splices forming the optical path between two terminal devices.

Cable Rack
The vertical or horizontal supports, usually made of aluminum or steel, that are attached to a ceiling or wall. Cables are laid in and fastened to the rack. Sometimes called trays.

Cable Riser
An assembly of one or more conductors within an enveloping sheath, constructed so as to permit use of the conductors singly or in groups.

Cable Routing Diagram
A detailed drawing showing the layout of the cable routes.

Cable Run
A length of installed media who may include other components along its path.

Cable Sealing Clamp
A device consisting of a gland nut and sealing member designed to seal around a single jacket cable. (MIL-STD)

Cable Sheath
A covering over the optical fiber or conductor assembly that may include one or more metallic members, strength members or jackets.

Cable Sheilding Clamp
A device consisting of a sealing member and cable support designed to terminate the screen (shield) of an electrical cable. (MIL-STD)

Cable Shield
A conductive layer of material located just under the cable’s outer sheath which is designed to increase the cable’s immunity to outside electrical noise interference. It may be constructed of metal foil or braided strands.

Cable Tray
A ladder, trough, solid-bottom or channel raceway system intended for, but not limited to, the support of telecommunications media (i.e., cable).

Cable Vulcanizer
Compression molding machine used to repair cable jacketing that has had apart removed for splicing, for adding connectors or other devices, or for replacing damaged sections.

Cable-in-Duct
System for direct burial in which a flexible conduit is extruded over electrical cables for a single pre-assembled unit.

Cable-Laid Wire Rope
A type of wire rope consisting of several wire ropes laid into a single wire rope

Cable, Clamp
A device used to give mechanical support to the wire bundle or cable at the rear of a plug or receptacle.

Cable, Coaxial
1) A cable consisting of two cylindrical conductors with a common axis separated by a dielectric. 2) A cable in the form of a central wire surrounded by a conductor tubing or sheathing that serves as shield and return.

Cable, Flat
1) Any cable with two smooth or corrugated but essentially flat surfaces. 2) Two or more parallel, round or flat, conductors that are contained in the insulating base material.

Cable, Flat Conductor
_A planar construction with tow or more flat conductors.

Cable, Flat, Margin
The distance between the reference edge of a flat cable and athe nearest edge of the first conductor.

Cable, Refernce Edge
The edge of a cable or conductor form which measurements are made.

Cable, Ribbon
1) A flat cable of individually insulated conductors lying parallel and held by adhesive film laminate. 2) A flat cable with round conductors.

Cable, Star Quad
A multi-core radio or television relay cable in which the conductors are arranged in quads and each quad consists of four conductors twisted together, the diagonally opposite conductors constituting a pair circuit. Also known as spiral four cable.

Cable, Transmission
Two or more transmission lines in the form of an interconnection-wiring cable.

Cable/Harness Outdoor Use
Outdoor Use Cables/Harnesses: Product expected to withstand elements of wheather.

Cable/Harness, Indoor Use
Product intended and designed for indoor use only.

Cabling
1) A combination of all cables, wire, cords and connecting hardware; 2) Twisting together two or more insulated conductors by machine to form a cable. In fiber optics, a method by which a group or bundle of fibers is mechanically assembled. 3) A system of telecommunications cables, cords and connecting hardware that can support the connection of information technology equipment. The twisting together of two or more insulated conductors to form an element.

Cabling Factor
Used in formulas for calculating the overall diameter of cable. D=fd where D=cable diameter, f=factor, and d=diameter of one conductor.

Caller ID
Calling Number Identification

Calorie
The quantity of heat required to raise 1 gram of water 1°C.

Camber
The planar deflection of a flat cable or flexible laminate from a straight line.

Campus
The building and grounds of a complex (i.e. a university, college, industrial park or military establishment). A premises containing more than one building adjacent or near to one another.

Campus Backbone Cable
The communications cable that is part of the Campus Backbone Subsystem and runs between building. There are four methods of installing campus backbone cable: in-conduit (in underground conduit), direct-buried (in trenches), aerial (on poles), and in-tunnel (in stream tunnels). A cable that connects the campus distributor to the building backbone distributor(s). Campus backbone cables may also connect building cabling distributors directly.

Campus Cable Entrance
The point at which Campus Backbone Subsystem cabling (aerial, direct-buried, or underground) enters a building.

Canadian Standards Association (CSA)
A non-profit independent organization which operates a listing service for electrical and electronic materials and equipment. The Canadian counterpart of the Underwriters Laboratories.

Capacitance
1)Storage of electrically separated charges between two plates having different potentials. The value depends largely on the surface area of the plates and the distance between them.__2)That property of a system of conductors and dielectrics which permits the storage of electricity when potential differences exist between the conductors. Its value is expressed as the ratio of a quantity of electricity to a potential difference, in farads (microfarads). A capacitance value is always positive.

Capacitance Coupling
Electrical interaction between two conductors caused by the potential difference between them.

Capacitance Direct
The capacitance measured directly from conductor to conductor through a single insulating layer.

Capacitance Mutual
The capacitance between two conductors with all other conductors, including shield, short circuited to ground.

Capacitance Reactance
The opposition to alternating current due to the capacitance of a capacitor, cable or circuit. It is measured in ohms and is equal to 1/6.28fC where f is the frequency in Hz and C is the capacitance in farads.

Capacitance Unbalance
The inequalities of the capacitances of the wires of a telephone circuit to other wires or to earth which will produce interference. Various forms of unbalance arise according to the circuits concerned in the measurement,

Capacitance Unbalance to Ground
An inequality of capacitance between the g round capacitance of the conductors of a pair which results in a pickup of external source energy, usually from power transmission lines.

Capacitance, Direct
The capacitance measured directly from conductor to conductor through a single insulating layer.

Capacitance, Mutual
The capacitance between two conductors with all other conductors, including shield, short circuited to ground.

Capacitive Coupling
Electrical interaction between two conductors caused by the capacitance between them.

Capacitive Reactance (Xc)
The opposition to alternating current due to the capacitance of the cable or circuit. Measured in ohms.

Capacitor
Two conducting surfaces separated by a dielectric material. The capacitance is determined by the area of the surfaces, type of dielectric and spacing between the conducting surfaces.

Capillary Action
The phenomenon of liquid rising in a small interstice due to surface tension. The effect of surface tension that draws a liquid into a small opening.

Carbon Black
Finely divided carbon used as a reinforcing filler in sealants.

Carrier
A continuous frequency capable of being modulated by an information carrying signal.

Carrier Frequency
The electromagnetic wave frequency selected to transmit information. Optical carrier frequency is from the infrared, visible range or ultraviolet spectrum areas.

Carrier Sense Multiple
Network access method using contention similar to Carrier Sense Multiple.

Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA)
Access/Collision Detection (CSMA/CD) used by LocalTalk networks. Unlike CSMA/CD, in this method the sending node requests permission to send from communications. It defines protocols for user or applications programs.

Carrier Sense Multiple Access/Collision Detection (CSMA/CD)
Network access method in which nodes contend for the right to send data. If two or more nodes attempt to transmit at the same time, they abort their transmission until a random time period of microseconds has transpired and then attempt to resend.

Carrier Signal
A continuous signal, upon which is modulated the data or other signal that is to be transmitted.

Carrier-to-noise ratio (CNR)
A quantification of analog system noise. The ratio, expressed in decibels, of the level of the carrier to that of the noise in the receiver bandwidth before any nonlinear process such as amplitude limiting and detection takes place.

Casein Adhesive
An aqueous colloidal dispersion of casein that may be prepared with or without heat, may contain modifiers, inhibitors, and secondary binders to provide specific adhesive properties, and includes a subclass, usually identified as casein glue, that is based on a dry blend of casein, lime, and sodium salts, mixed with water and prepared without heat.

Catalyst
A reactive material added to accelerate adhesive drying. Substance added in small quantities to promote a reaction, while remaining unchanged itself.

CATEGORY 3 (CAT 3)
Category 3 cable, commonly known as Cat 3 or station wire, and less commonly known as VG or Voice-grade (as, for example, in 100BaseVG), is an unshielded twisted pair (UTP) cable used in telephone wiring.

CATEGORY 4 (Cat 4)
Category 4, commonly known as Cat 4, is a cable that consists of four unshielded twisted-pair (UTP) copper wires with a data rate of 16 Mbit/s and performance of up to 20 MHz. It is used in telephone networks which can transmit voice and data up to 16 Mbit/s.

CATEGORY 5 (CAT 5)
Category 5 cable, commonly referred to as Cat 5, is a twisted pair cable for carrying signals. This type of cable is used in structured cabling for computer networks such as Ethernet. The cable standard provides performance of up to 100 MHz and is suitable for 10BASE-T, 100BASE-TX (Fast Ethernet), and 1000BASE-T (Gigabit Ethernet). Cat 5 is also used to carry other signals such as telephony and video. This cable is commonly connected using punch-down blocks and modular connectors. Most category 5 cables are unshielded, relying on the balanced line twisted pair design and differential signaling for noise rejection.

CATEGORY 5e (CAT 5e)
Category 5e specification improves upon the category 5 specification by tightening some crosstalk specifications and introducing new crosstalk specifications that were not present in the original category 5 specification.[13] The bandwidth of category 5 and 5e is the same (100 MHz)[14] and the physical cable construction is the same, and the reality is that most Cat5 cables meet Cat5e specifications, though it is not tested or certified as such

CATEGORY 6 (CAT 6)
Category 6 cable, commonly referred to as Cat 6, is a standardized cable for Gigabit Ethernet and other network physical layers that is backward compatible with the Category 5/5e and Category 3 cable standards. Compared with Cat 5 and Cat 5e, Cat 6 features more stringent specifications for crosstalk and system noise.

CATEGORY 7 (CAT 7)
Category 7 cable standard has been created to allow 10 Gigabit Ethernet over 100 m of copper cabling (also, 10 Gbit/s Ethernet now is typically run on Cat 6A). The cable contains four twisted copper wire pairs, just like the earlier standards. Category 7 cable can be terminated either with 8P8C compatible GG45 electrical connectors which incorporate the 8P8C standard or with TERA connectors. When combined with GG45 or TERA connectors, Category 7 cable is rated for transmission frequencies of up to 600 MHz.[1]

CATEGORY 7A
Category 7A cables, introduced by ISO 11801 Edition 2 Amendment 2 (2010), are defined at frequencies up to 1000 MHz, suitable for multiple applications including CATV (862 MHz). Each pair offers 1200 MHz of bandwidth.

CATEGORY 8
Category 8, which will use the standard 8P8C connector. Category 8 should be fully backward compatible with Category 6A and below, and will be covered by ANSI/TIA-568-C.2-1 "Specifications for 100? Category 8 Cabling".

Cathode
The electrode in a device that electrons flow into. In a battery or other source of direct current the cathode is the positive terminal, but in a passive load it is the negative terminal._

Cation
Any positive ion (Examples: Li+, Ca2+)

Cationic polymerization
an ionic polymerization in which the kinetic-chain carriers are cations. (IUPAC)

Caul
A sheet of material employed singly or in pairs in hot or cold pressing of assemblies being bonded.

Caulking
See sealant

Caulking compound
See sealant

Cdma2000 1xEV
The EV means “Evolution”

Cdma20001xEV-DO
The 1xEv-DoO means “1x-Evoltion-Data Optimized” (or Evolution- Data Only)

Cdma20001xEV-DV
The EV-DV means “1xEvolution-Data and Voice”

Cdma20001xRTT
The RTT means single carrier Radio Transmission Technology

Ceiling Distribution
Distribution system that uses the space between the false or suspended ceiling and the structural ceiling for housing horizontal cable routes.

Cell
The geographic area served by a single low-power transmitter/receiver. A cellular system’s service area is divided into multiple "cells". Cells can vary in size depending on terrain, capacity demands, etc. By controlling the transmission power, the radio frequencies assigned to one cell can be limited to the boundaries of that cell.

Cell Relay
A fast packet switching technique which uses fixed-length cells. Generic name for ATM, SMDS and BISDN.

Cell Site
The location where communications equipment is located for each cell. A cell site usually includes antennas, a support structure for those antennas, and communications equipment to connect the site to the rest of the wireless system.

Cell Splitting
A method of increasing the capacity of a wireless system by subdividing or splitting cells into two or more smaller cells.

Cellular Digital Packet Data (CDPD)
Introduced in 1992 by McCaw Cellular, IBM and a group of eight other major cellular companies, CDPD uses the idle time in the analog cellular-telephone system to transmit packetized data at rates up to 19.2 kb/s.

Cellular Insulation
Insulating material in foamed or sponge form with the cells closed or interconnected.

Cellular material
A material containing many small cells dispersed throughout it. The cells may be either open or closed.

Cellular Plastics
Expanded or foam, consists of individual closed cells of inert gas suspended in a plastic medium, resulting in a desirable reduction of the dielectric constant.

Cellular Polyethylene
Expanded or "foam" polyethylene consisting of individual closed cells suspended in a polyethylene medium. Often found as dielectric material in coaxial cable.

Cellulose
a natural polymer found in wood and other plant material.

Cenelec
European committee for electrotechnical standardization.

Center Conductor
The inner conductive member in a coaxial structure, such as center contacts.

Center wavelength (CW)
The nominal value operating wavelength in a laser; thereby, the wavelength defined by a peak mode measurement where the effective optical power resides. Also, the average of the two wavelengths measured at half amplitude points of the power spectrum in lasers and LEDs.

Centers
Wire, strand or fiber in the center of a strand about which the wires are laid

Central Member
A material located in the middle of a cable that provides extra strength and anti-buckling properties.

Central Office
The place where communications common carriers terminate customer lines and locate switching equipment that interconnects those lines.

Central Processing Unit (CPU)
A personal computer's (PC's) primary microprocessor chip.

Central strength member (CSM)
A semi-rigid, fibered glass or metallic rod located in the center of a multifiber cable assembly. Usually referred to as dielectric, it provides a directional form for wrapping and stability. This inhibits the buffers from being damaged (stressing the fibers) during the bending of the cable.

Centralized cabling
A cabling configuration from the work area to a centralized cross-connect using pull-through cables, an interconnect or splice in the telecommunications room.

Centrex
The switching system of a local telephone operator.

Certificate of Compliance (C of C)
A certificate which is normally generated by a Quality Control Department, which shows that the product being shipped meets customer's specifications.

Certified Test Report (CTR)
A report providing actual test data on a cable. Tests are normally run by a Quality Control Department, which shows that the product being shipped conforms to test specifications.

Chain
the whole part of part of a macromolecule (or oligomer molecule or block) comprising a sequence of constitutional units between two boundary constitutional units, each of which may be either an end-group or a branch point. Except in linear single-strand macromolecules, the definition of the chain may be somewhat arbitrary. A cyclic macromolecule has no end groups but may nevertheless be regarded as chain. Where appropriate, definitions relating to "macromolecule" may also be applied to "chain". (IUPAC)

Chain polymerization
a chain reaction in which the growth of a polymer chain proceeds exclusively by reaction(s) between monomer(s) and reactive site(s) on the polymer chain such that the reactive site(s) are regenerated on the same polymer chain by the end of each growth step. A chain polymerization consists of initiation and propagation reactions, and may also include termination and chain transfer reactions. The adjective "chain" in "chain polymerization" denotes "chain reaction". In a chain polymerization, the average degree of polymerization remains constant with monomer conversion (e.g., in steady-state, radical polymerizations) or may increase with monomer conversion (e.g., in the formation of living polymers). (IUPAC)

Chain stopper
A material added during the polymerization process to terminate or control the degree of the reaction. This could result in soft sealants, or higher elongation.

Chain transfer
A chemical reaction, usually occurring during chain polymerizations, in which the activity of the kinetic-chain carrier is transferred from the growing macromolecule or oligomer molecule to another molecule or another part of the same molecule. Chain transfer to another part of the same molecule is often termed backbiting. (IUPAC)

Chalking
The preventing of the proper coalescence of the adhesive film due to low temperatures of the air, wood or adhesive.

Changing Current
The current produced when a D.C. voltage is first applied to conductors of an unterminated cable. It is caused by the capacitive reactance of the cable, and decreases exponentially with time.

Channel
A communications path or the signal sent over that path. Through multiplexing several channels, voice channels can be transmitted over an optical channel.

Channel glazing
The method of glazing in which lites are set in a channel formed by two stops

Channel Link
The Channel Link includes up to 90 m (295 ft) of horizontal cable, a work area patchcord, a telecommunications outlet/connector, an optional transition point or consolidation connector, and two connections in the telecommunications room. When a maximum horizontal length of 90 m is used, then the total length of the patchcords shall not exceed 10 m (33 ft). For other lengths of horizontal cabling, refer to ANSI/EIA/EIA-568-B.2.

Channel Service Unit
A device that interfaces a digital telephone line to a multiplexer or other digital device for high-speed communications.

Character
A combination of binary digits representing an alphanumeric value.

Character Oriented Protocol
A communications protocol that responds to special control characters as opposed to individual bit values for function control.

Characteristic Impedance
Characteristic Impedance is the measure of a transmission medium’s impedance throughout its length and over a swept frequency spectrum. When terminating transmission media, it is important to match its Characteristic Impedance so as to minimize reflections.

Charge
The quantity of electricity held statically in a condenser or on an insulated conductor.

Charging Current
The current produced when a DC voltage is first applied to conductors of an unterminated cable. It is caused by the capacitive reactance of the cable, and decreases exponentially with time.

Checking
The formation of slight breaks or cracks in the surface of the adhesive.

Chemical cure
Curing by chemical reaction. Usually involves the crosslinking of a polymer.

Chemical Resistance
The ability of the insulation to withstand exposure to and resist damage by chemicals and substances. Exposure can range from immersion to occasional contact. Six basic types of chemicals are: Acid: can be organic or inorganic; have a tendency to dissociate in water to partially or completely ionized in solution; typical organic acids are citric acid, carbonic acid, hydrogen cyanide, lactic acid and salicylic acid; typical inorganic acids are sulfuric acid, phosphoric acid, nitric acid, hydrogen sulfide and hydrocholir acid. Alchols: organic compounds with the general formula R-OH, in which R represents an alkyl group and -OH represents one or more hudroxl groups; typical compounds are methanol, ethanol, glycols and isopropanol; used in antiseptics, cough syrups, medications, cleaners, coating, shellac, dyes, inks, fuel additives, cosmetics, perfumes and as base materials for plasticizers synthetic lubricants. Aliphatic hydrocarbons; organic compounds whose carbon atoms are joined in straight or branched chains instead of rings; typical compoiuns are mineral spirits, paint thinner, petroleum distillate, and cyclohexane; found in oil and alkyd based coatings, pesticides, furniture oils, cleaners and som cosmetics. Alkalis: hydroxides of an alkali metal (lithium, sodium, potassium, rubidium, cesium, francium, beryllium, magnesium, calcium, strontium, barium, radium); easily soluble in water and form basic solutions, neutralizes acids, forming salts and water; typical alkalis are sodium hydroxide, sodium bicarbonate, calcium hydroxide and calcium carbonate. Aromatic hydrocarbons: organic compounds that contain at least one ring of six carbon atoms, each joined to at least two other carbon atoms; typical compounds are toluene, xylene, phenol, benzene, and styrene; found in enamel paints, paint strippers, some lacquer coatings, in gaseoline, in engine cleaners, in styrenic plastics, phenolic resins, creosol perservatives and some pesticides. Oils: describes a variety of greasy fluid substances that are typically viscous liquids at room temperature, less dense than water, insoluble in water but soluble in alcohol and usually flammable; the wide range of compositions make generalizations not useful, but they can be grouped; groupings would be petroleum/hydrocarbons, fats/oils, and volatile oils; petroleum/hydrocarbons are used as fuels, solvents, and lubricants; fats/oils are used in soaps, lubricants. There are other additional types not listed.

Chemtrec
Chemical Transportation Emergency Center. Provides emergency information on materials involved in transportation accidents.

Chlorinated Polyethylene (CPE)
A polymerized ethylene resin that has been treated or combined with chlorine or a chlorine compound; A synthetic rubber jacketing compound.

Chlorosulfonated Polyethylene (CSPE)
A rubbery polymer used for insulations and jackets. Manufactured by Dupont under the tradename of Hypalon.

Choker
Short wire rope sling used to form a slip noose around the object to be moved or lifted

Chroma
The color information contained in a color video signal.

Chroma Keying
The process of inserting one color video signal into another color video signal.

Chromatic Dispersion (CD)
Spreading of a light pulse caused by the difference in refractive indices at different lengths; The variation in the velocity of light (group velocity) as a function of wavelength. It causes pulses of a modulated laser source to broaden when traveling within the fiber, up to a point where pulses overlap and bit error rate increases. CD is a limiting factor in high-speed transmission and must be properly compensated, which implies proper testing. A combination of material and waveguide dispersion.

Churn
The relocation of an individual or a group of individuals within a building such that the workspace or services to the workspace require change.

Cigarette Wrap
Tape insulation wrapped longitudinally instead of spirally over a conductor.

Circuit
A complete path over which electrons can flow from the negative terminals of a voltage source through parts and wires to the positive terminals of the same voltage source. When the continuity of the circuit is broken it is called an open circuit: when con

Circuit Sizes
A popular term for building wire sizes 14 through 10 AWG .

Circuit-Switched Data
Circuit-switched data involves keeping a circuit open between users for the duration of a connection.

Circular Mil
The area of a circle one mil [0.001 in] in diameter; 7.845 x 10¨7 sq. in. Used in expressing wire cross sectional area.

Circular Mil Area (CMA)
The square of a conductor diameter in mils, of thousandths of an inch. Example a 30 AWG conductor has a diameter of 10 mils and a CMA of 100. Used to determine conductor sizes.

Circumferential Crimp
The type of crimp where the crimping dies completely surround a barrel, resulting in symmetrical indentations in the barrel. (MIL-STD)

Cladding
The low refractive index optical coating surrounding the core of a fiberoptic cable that prevents light from escaping the core. The cladding guides light along the core.

Cladding (Fiber Optic)
A layer of glass (or other material) surrounding the core of a fiber, forming the conduit that carries the light through the fiber. It has a refractive index slightly lower than the core.

Clamp Carrier
A series of cold clamps arranged and used like a Ferris wheel. This permits a large number of panels to be clamped and stored within a small area.

Clamp Time
The period of time required for a joint to gain enough strength to permit it to be removed from pressure with no decrease in long-term strength.

Clamping
Tying tapes, lacing cords, and flexible sleevings which are used for wire and cable bundling, harnessing, and holding. Other devices include plastic ties or clamps, spiral-cut plastic tubing, and plastic U-shaped trays or ducts.

Clamping Force
The total force exerted by a clamping device on a glue line.

Clamping Voltage
Underwriters Laboratories (UL) rates the clamping voltage of surge protectors. The lower the rating, the better the protection.

Cleavage
In an adhesively bonded joint, a separation in the joint caused by wedge or other crack-opening type action.

Cleavage strength
The force per unit width of bond line required to produce progressive separation by wedge or other crack-opening type action of two adherends.

Cleave
A technique where an optical fiber is scratched to produce flat end surfaces that are perpendicular to the longitudinal axis of the fiber. See scribe.

Cleave and crimp
A connector installation technique, also known as a no-polish connector. The plug is installed onto the cable with the optic protruding from the end. The cable is crimped to the connector and the optic is cleaved as close to the connector endface as possible.

Cleave tool
A device consisting of a scribing blade, usually made from either diamond or tungsten carbide, used to score a fiber in order to break it without causing a fracture, hackles or angular irregularities. Also known as a cleaver or scribe tool.

Client
A node that requests network services from a server.

Client-Server
A technique by which processing can be distributed between nodes requesting information (clients) and those maintaining data (servers).

Clip
Fitting for clamping two parts of wire rope

Clock
In data communications, a device that generates precisely spaced timing pulses used for synchronizing transmissions and recording elapsed times.

Clocking
Mechanical arrangement of keyways, inserts or grooves in a connector shell or insert that allows connectors of the same configuration to be used without the danger of interconnection to the wrong mating connector. Also called Keying.

Clorosulfonated Polyethylene (CSPE)
A rubbery polymer used for insulations and jackets. Manufactured by DuPont under the trade name of Hypalon.

Closed Assembly Time
Period of assembly time when the adhesive film is not exposed to the air, but prior to the time that pressure has been applied.

Closed cell
A cell enclosed by its walls and therefore not connected to other cells.

Closed cell material
A cellular material in which substantially all cells in the mass are closed cells.

Closed circuit television (CCTV)
Video transmissions not provided for public access.

Closed End Splice
An insulated splice in which two or more wires overlap and enter the splice from the same end of the barrel.

Closed Entry
A contact or contact cavity design in the insert or body of the connector which limits the size or position of the mating contact or printed circuit board to a predetermined dimension. (MIL-STD)

Closed Entry Contact
A specially designed connector interface which controls the entry of the male pin from damaging the female contact.

Closet
SYSTIMAX® SCS location for hardware, conduits, power panels, and electronics, such as multiplexers and concentrators.

Closet, Telecommunications
An enclosed space for housing telecommunications equipment, cable terminations, and cross-connect cabling. The closet is the recognized location of the cross-connect between the backbone and horizontal facilities.

Closing
An operation where all leads are to be covered and the jacket insulations is captured by a type of hood or cover.

Closure
See splice closure.

Co-Location
The siting of two or more separate companies’ wireless antennas on the same support structure.

Co-oligomer
An oligomer derived from more than one species of monomer. (IUPAC)

Co-oligomerization
Oligomerization in which a co-oligomer is formed. (IUPAC)

Coarse wavelength division multiplexing (CWDM)
Applies to greater separation of wavelengths than DWDM. In single-mode applications, CWDM defines a 20-nm separation from 1471 nm to 1611 nm. With multimode fibers, the wavelengths are 778, 800, 825, and 850 nm.

Coating
A material applied to the surface of a conductor to prevent environmental deterioration, facilitate soldering or improve electrical performance.

Coaxial
A cable that consists of two conductors laid concentrically along the same axis. One conducting wire is surrounded by a insulator, which is in turn surrounded by the other, outer conductor. The whole cable is wrapped in a protective plastic sheathing. Coaxial is frequently shortened to Coax (Co-ax)_

Coaxial Cable (Coax)
1)A cable consisting of two cylindrical conductors with a common axis, separated by a dielectric.__2)A wide-band cable consisting of an inner conductor a dielectric and a concentric outer shield. Coaxial cable is usually specified as to characteristic impedance, frequency response and propagation delay.__3)A cable consisting of one center conductor to carry a signal, surrounded concentrically (coaxially) by an insulating dielectric and a separate outer conductor (braid or metal jacket) which acts as a shield for the signal.

Coaxial Connector
A connector that has a coaxial construction and is used with coaxial cable.

Coaxial Contact
A contact having two conducting surfaces, a center contact and a coaxially placed sleeve.

Coaxial Line
A transmission line consisting of a center conductor suspended in a hollow cylindrical tube with or without a dielectric support. The hollow cylindrical tube is called the outer conductor.

CODE-Division Multiple Access (CDMA)
CDMA is a digital technology that uses a low-power signal "spread" across a wide bandwidth. With CDMA a phone call is assigned a code rather than a certain frequency. Using the identifying code and a low-power signal, a large number of callers can use the same group of channels. Some estimates indicate CDMA’s capacity increase over analog may be as much as 20 to one. The Telecommunications Industry Association has awarded CDMA inter-standard approval (IS-95).

Coefficient of expansion
The coefficient of linear expansion is the ratio of the change in length per degree to the length at 0°C.

Coherence
Lasers and LEDs emit coherent light waves that are in phase with one another. Coherence describes properties of the correlation between a single wave, or between several waves or wave packets. When interfering, two waves can add together to create a wave of greater amplitude than either one (constructive interference) or subtract from one another to create a wave of lesser amplitude than either one (destructive interference).

Coherent Source
A light source which emits a very narrow, unidirectional beam of light of one wavelength (monochromatic).

Coherent Waves
The phenomenon related to the existence of a correlation between the phases of the corresponding components of two waves or between the values of the phase of a given component of one wave at two instants in time or two points in space.

Cohesion
The molecular attraction which holds the body of an adhesive together. The internal strength of an adhesive.

Cohesion (cohesive) failure
Rupture of a bonded assembly in which the separation appears visually to be in the adhesive or the adherend.

Cohesive Blocking
See blocking.

Cohesive Failure
Condition of bond failure in which the adhesive falls apart.

Cohesive Strength
The ability of the adhesive to stick within itself during the wet stage. The term cohesive strength also applies to the internal strength of dried adhesive.

Coil
A conductor wound into a helical/configuration of uniform cross-section.

Coil Effect
The inductive effect exhibited by a spiral-wrapped shield, especially above audio frequencies.

Coiled Cord
Cable formed into the shape of a spring by winding cable around a mandrel, and heat set into the shape (also referred to as retractile cordset). This permits the extension of a coiled cord to a length from 3 to 5 times it's length at rest. A coiled cord will typically return , after being extended and released, to a length similar to it's original length at rest.

Cold Bend
A laboratory test procedure whereby a sample of wire or cable is wound around a mandrel of a specified size at a specified temperature for a given number of turns at a given rate of speed and examined for defects.

Cold Blend
Test conducted by rapping tubing around a mandrel or by bending it in a arc while at a low temperature

Cold Blend Test
Test to measure a cable's ability to withstand cold temperature.

Cold Flow
1)Permanent deformation of insulation due to mechanical forces, without the aid of heat-softening of the insulating material.__2)Deformation of the insulation due to mechanical force or pressure (not due to heat softening).

Cold Joint
A soldered joint made with insufficient heat.

Cold Press
A hydraulic or pneumatic press designed to press face-glued or veneered panels without the addition of heat.

Cold pressing
A bonding operation in which an assembly is subjected to pressure without the application of heat.

Cold Test
Any test to determine the performance of cables during or after subjection to a specified low temperature for a specified time.

Cold Work
The hardening and embrittlement of a metal by repeated flexing action.

Cold-setting adhesive
An adhesive that sets without the application of heat.

Collapsed Backbone
This architecture is a backbone topology where wiring concentrators located at floor levels are attached in a star configuration to a central high performance switching concentrator.

Collimation
A process in which a divergent or convergent beam of radiation is converted into a beam with the minimum divergence as possible, preferably parallel.

Collision
The event that occurs when data from two devices attached to a common bus are placed on the bus at the same time. In Ethernet this typically generates a re-transmission.

Colophony
See rosin.

color
The particular color of a tape, when looking at the backing, regardless of the color of the adhesive.

Color Burst
8 to 10 cycles of 3.68 MHz subcarrier that is added to the back porch of the Horizontal Sync Pulse. The Color Burst is used to synchronize the color elements of a color video signal.

Color Code
A color system for wire or circuit identification by use of solid colors, stripes or surface operating

Color Coding
A system of identification of terminals and related devices. (MIL-STD)

Color Phase
The timing relationship between the Luminance and chroma portions of a composite color video signal.

Color Stability
The ability of a tape to retain its original color, particularly when exposed to light.

Color Subcarrier
The 3.58 MHz subcarrier which conveys color information.

Comb Macromolecule
A macromolecule comprising a main chain from which long chains emanate at approximately regular intervals. (IUPAC)

Comb Polymer
A substance composed of comb macromolecules. (IUPAC)

Combustible
Materials that will burn

Come-along
Device for making a temporary grip on a wire rope

Commercial Building
A building or portion thereof, that is intended for office use.

Commercial Mobile-Radio Service
The regulatory classification that the Federal Communications Commission uses to govern all commercial wireless service providers, including personal communications services, cellular, and enhanced specialized mobile radio.

Common Axis Cabling
In multiple cable constructions, a twisting of all conductors about a common axis with two conductor groups then selected as pairs. This practice yields smaller diameter constructions than does a separate axis construction, but tends to yield greater sus

Common Carrier
An organization that provides regulated telephone, telegraph, telex and data communications systems.

Common Mode
Noise caused by a difference in ground potential. By grounding at either end rather than both ends (usually grounded at source) one can reduce this interference.

Common Mode Current
The component of the signal current that induces electric and magnetic fields that do not cancel each other. For example; in circuit with one outgoing signal conductor and one ground conductor, the common-mode current is the component of the total signal current that flows in the same direction on both conductors. This is the primary source of EMI in many electronic systems.

Common Mode Interference
Interference appearing between signal leads or the terminals of a measuring circuit and ground.

Common Mode Rejection Ratio
The ratio of the common-mode interference voltage at the input of a circuit to the corresponding interference voltage at the output. This ratio expresses the capability of the device to reject the effect of a voltage that is applied simultaneously to both input terminals. A high ratio is desirable.

Common Strand
Galvanized strand made of galvanized iron wire whose grade is common iron

Communications
The electronic transfer of information between the points of origin and reception. Includes all manual and machine interfaces necessary to complete the transfer.

Communications Common Carrier
In the U.S., a government-regulated private company that furnishes the general public with telecommunications service facilities; for example, a telephone or telegraph company.

Communications Network
A complex of data communications equipment, data links and channels that connect one or more data processing systems.

Communications Protocol
The rules that govern the behavior and attributes of both hardware and software as they apply to data communications.

Communications Server
A device which acts as a gateway to communication lines outside normal building boundaries or to a different communicating device. The server may allow access to several lines by any number of users on a network. Sometimes called a modem pool.

Community antenna television (CATV)
Assumed to be cable television, CATV uses fiber and coaxial media to provide voice, video, or data services.

Compact Conductor
Stranded conductor rolled to deform the round wires to fill the normal interstices between the wires in a strand.

Compatibility
The ability of dissimilar materials to exist in mutual proximity or contact without changing their physical or electrical properties.

Competitive local exchange carrier (CLEC)
A company that provides its own network and switching in competition with the already-established ILEC. A newly formed exchange company in direct competition with the ILEC for the telecom transport market in a specific area. Also known as competitive access provider (CAP).

Component
A basic electronic element usually packaged in a discrete form with two or more connecting leads or metallic pads. Components are intended to be connected together, usually by soldering to a printed circuit board, to create an electronic circuit._

Composite (Clad) Wire
A wire having a core of one metal with a fused outer shell of different metals.

Composite Cable
A cable consisting of two or more different types or sizes of wires.

Composite Conductor
Two or more strands of different metals assembled and operated in parallel.

Composite Polymer
A filled or reinforced plastic

Composite second order (CSO)
An analog signal distortion that can result in a visual impairment in picture quality, e.g., a rolling or intermittent diagonal line across the TV screen.

Composite Sync
A mixed signal consisting of Composite Sync, Color Burst and Video.

Composite triple beat (CTB)
Combination of distortions caused by nonlinearities generated by amplifiers and other components in a cable TV network handling many RF signals.

Compositional Heterogeneity
The variation in elemental composition from molecule to molecule usually found in copolymers. (IUPAC)

Compound
An insulating or jacketing material made by mixing two or more ingredients.

Compression
Any technique for reducing a transmission bandwidth requirement by reduction of the data stream needed to convey the information. Compression standards are identified by MPEG.

Compression Cable
A pipe type cable in which the pressure medium is separated from the insulation by a membrane or sheath.

Compression Connector
Connector crimped by an externally applied force; the conductor is also crimped by such force inside the tube-like connector body. Compression connectors are in very intimate contact with the two ends of the conductors being spliced.

Compression Molding
A method of molding thermosets. Compound (usually preheated) is placed in an open mold, mold is closed, and heat and pressure applied until material is cured. This process can also be used with synthetic rubber materials.

Compression Seal
A seal which is attained by a compressive force on the sealing material.

Computer Network
A collection of computers connected by a data communications network.

Computer Telephony
The adding of computer intelligence to the making, receiving and managing of telephone calls.

Concentration
The function of routing information from a number of communications links into a smaller number of higher capacity links and providing the reverse flow from fewer to more links. A device which performs this function usually is called a concentrator. Unlike the multiplexer, the concentrator is a programmable device.

Concentrator
Programmable device which routes information from a number of communications links into a smaller number of higher capacity links and provides the reverse flow from fewer to more links.

Concentric
A central core surrounded by one or more layers of helically wound strands in a fixed round geometric arrangement.

Concentric lay
Cable conductor composed of a central conductor surrounded by one or more layers of helically laid insulated wires or conductors.

Concentric Strand
A wire that consists of a central wire or core surrounded by one or more layers of spiral laid wires.

Concentric Stranded Conductors
Manufactured to ASTM, ICEA, and CSA standards. The most common fixed installation type conductors are : 1) Round-no diameter reduction: 2) Compressed-approximately 3% diameter reduction; 3) Compact-approximately 10% diameter reduction.

Concentric Stranding
1)A central wire surrounded by one or more layers of helically wound strands in a fixed round geometric arrangement.__2)Stranding in which the individual filaments are spiraled in layers around a central core. As a general rule, each layer after the first has six more strands than the preceding layer and is applied in a direction contra-helical to that of the layer under it.

Concentric-Lay Cable
A concentric-lay conductor, or a multiple-conductor cable composed of a central core surrounded by one or more layers of helically laid insulated conductors.

Concentricity
In a wire or cable, the measurement of the location of the center of the conductor with respect to the geometric center of the insulation. Expressed in percent.

Condensation
A chemical reaction in which two or more molecules combine with the separation (or release) of water or some other simple substance. If a polymer is formed, the process is called polycondensation.

Condensation Polymer
One in which two or more molecules combine resulting in elimination of water or other simple molecules, with the process being repeated to form a long chain molecule.

Conditioning Time
See joint conditioning time. (See also curing time and setting time.)

Conditions, Ambient
Temperature, humidity, sunlight, etc. which exist in the area surrounding the bond, normally room temperature, atmospheric pressure, daylight, etc.

Condnsation Polymerization
A reaction in which monomer molecules with at least two functional groups combine and eliminate water (or some other simple molecule) to form a polymer

Conductance
1)The reciprocal of resistance. It is the ratio of current passing through a material to the potential difference at its ends.__2)The ability of a conductor to carry an electrical charge. The ratio of the current flow to the potential difference causing the flow. The reciprocal of resistance.

Conducted Emission
The potential EMI generated inside equipment and carried through the I/O lines, the power lines or control leads.

Conducted Susceptibility
The EMI that couples from the outside of equipment to the inside of equipment over the I/O cables, power lines or signal leads.

Conductive Elastomer
A rubber-like material containing metal powder or small particles for conducting electricity to achieve a specified shielding effectiveness.

Conductivity
The capacity of a material to carry electrical current that is usually expressed as a percentage of copper conductivity (copper being 100%).

Conductor
1)An electric current carrying material such as copper wire; the conductive element in an electrical wire or coaxial connector.__2)An insulated wire suitable for carrying electrical current.__3)A conductor is a slender rod or filament of drawn metal of circular cross section or group of such rods or filaments not insulated from one another, suitable for transmitting an electric current.

Conductor Material
A type of metal used to make wire for conductors. The most commonly used material is ETP copper (usually referred to as copper). A special grade of copper is OFHC copper, which is oxygen-free, high conductivity copper. Alloys of copper are used for applications needing higher strength or longer flex life or greater reliability. These alloys are normally Cadmium bronze (also known as Cadmium copper). Less frequently used alloys are Cadmium chromium copper, phosphor bronze, and Silicone bronze.

Conductor Shield
An extrusion of black semi-conducting thermoses material over the conductor to provide a smooth interface with the insulation for even distribution of electrical stress.

Conductor Stop
A device on a terminal, splice, contact or tool used to prevent excessive extension of the conductor barrel.

Conductor Stranded
Solid wires twisted together or groups of twisted solid wires which are then twisted together. The most common types of stranded conductors are 7 twisted wires (7 strand), or 16 twisted wires (16 strand), or 19 twisted wires (19 strand). Other strandings are 37 twisted wires 63 twisted wires, and 127 twisted wires. Concentric stranded conductors are twisted in progressive layers of 6 wires around 1 wire (7 strand), or 12 wires around 6 wires around 1 wire (19 strand) and 18 wires around 12 wires around 6 wires around 1 wire (37 strand). Bunch stranded conductors are twisted together at one time rather than in layers. Buch stranded conductors are typically either 16, 19, 26, 28, 37 or 40 twisted wires. The finished AWG (guage) of a conductor is determined by the number of strands (of wire) based on the AWG of the wire itself. For example, 7 strands of a 34 AWG wire will result in a 26 AWG conductor. A complete listing of the strand and AWG combinations can be found in our Stranded Conductors Chart.

Conductor, Flat
A rectangular conductor that is wider than it is high.

Conduit
A pipe made of metal, plastic, or clay used for the installation of communications or power cables between two or more locations.

Conduit (Electrical Raceway)
A rigid or flexible metallic or non-metallic raceway of circular cross section through which wire and cables can be pulled or housed.

Cone Penetrometer
An instrument for measuring the relative hardness of soft deformable materials.

Configuration
The number, spacing and arrangement of contacts in a connector. (MIL-STD). Related chemical structure produced by the making and breaking of primary valence bonds.

Configurational Base Unit
A constitutional repeating unit in a regular macromolecule (or oligomer or block), the configuration of which is defined at least at one site of stereoisomerism in the main chain. (IUPAC)

Configurational Repeating Unit
The smallest set of successive configurational base units that prescribes configurational repetition at one or more sites of stereoisomerism in the main chain of a regular macromolecule (or oligomer or block). (IUPAC)

Configurational Sequence
The whole or part of a chain comprising one or more species of configurational units in defined sequence. Note configurational sequences comprising two configurational units are termed diads, those comprising three configurational units triads, and so one. In order of increasing sequence lengths they are called tetrads, pentads, hexads, heptads, octads, nonads, decads, etc. (IUPAC)

Configurational Unit
A constitutional unit having at least one site of stereoisomerism. (IUPAC)

Confined Crimp
A crimp that remains in the confines of the outer diameter of the original barrel.

Conformability
The ability of tape to fit snugly or make essentially complete contact with the surface of an irregular object without creasing or folding.

Conformable Cable
See Semi-Flexible Cable.

Conical Drum
Grooved hoisting drum of tapering diameter

Connecting Block
A flame-retardant plastic block containing metal wiring terminal (quick clips) that establishes an electrically tight connection between the cable and the cross-connect wire; An interconnecting device used in telecommunications and LAN applications consisting of multiple points for wire attachment. Some common connecting blocks are the 66 block, 110 block, the BIX block and the Krone block.

Connecting Hardware
1) A device providing mechanical cable terminations between two cable ends; 2) See Cross Connect.

connections
The continuous electrical path between 2 or more points wherein current flows. The path is constructed with metal parts, such as copper wire, contacts, terminations, splices, and mating contacts of connectors.

Connector
A device used to physically and electrically connect two or more conductors. Also used to physically connect cable to equipment.

Connector Assembly
Includes housing and contact plus additional components such as hardware used to hold the assembly together and/or make the assembly a functional connector.

Connector Discontinuity
An ohmic change in contact resistance.

Connector Electrical
A device, whether a plug or a receptacle, used to terminate or connect the conductors of wires (individual or in cables) and which provides a means to continue the conductors to a mating connector or printed circuit board. (MIL-STD).

Connector Insert
That part which holds the contacts in their proper arrangement and electrically insulates them from each other and from the shell.

Connector Insertion Loss (Attenuation)
The loss of power in a mated pair of connectors.

Connector Return Loss
Amount of power reflected from the connector to connector interface, typically expressed in decibels.

Connector Set, Electrical
Two or more separate connectors, plug connector and receptacle connector, designed to be mated together. The set may include mixed connectors mated together, such as one connector plug and one dummy connector receptacle, or a connector receptacle and one electrical plug. (MIL-STD).

Connector Shell
The outside case of a connector into which the dielectric material and contacts are assembled. (MIL-STD)

Conrol Cable
A multiconductor cable made for operation in control or signal circuits.

Consignment
A process where customers provide the manufacturer with all the parts and materials. The manufacturer then builds the products and deliver completed assemblies or cables to the customer. Sometimes referred to as kitted._

Consistency
The property of a liquid adhesive by virtue of which it tends to resist deformation.

Consolidation
A step during the optical fiber manufacturing process during which the bait rod is removed and the remaining silica is heated at high temperatures (sintering) to drive out impurities and water and leave only a pure glass rod.

Consolidation Point
A location for interconnection between horizontal cables extending from a telecommunications room and horizontal cables extending to telecommunications outlet/connectors.

Constantan
An alloy used in making thermocouples wires. An alloy of copper, nickel manganese and iron.

Constitutional Heterogeneity
The variation in constitution from molecule to molecule in polymers with molecules uniform with respect to elemental composition. (IUPAC)

Constitutional Repeating Unit
The smallest constitutional unit, the repetition of which constitutes a regular macromolecule (or oligomer molecule or block). (IUPAC)

Constitutional Sequence
The whole or part of a chain comprising one or more species of constitutional units in defined sequence. Note constitutional sequences comprising two constitutional units are termed diads, those comprising three constitutional units triads, and so one. In order of increasing sequence lengths they are called tetrads, pentads, hexads, heptads, octads, nonads, decads, etc. (IUPAC)

Constitutional Unit
An atom or group of atoms in a macromolecule or oligomer molecule, comprising a part of the chain together with its pendant atoms or groups of atoms, if any. (IUPAC)

Construction
Design of wire rope including number of strands, number of wires per strand and arrangement of wires in each strand

Contact
The conductive element in a connector which makes actual contact for the purpose of transferring electrical energy. (MIL-STD) Generally, in a male connector the contact is a pin and in a female connector it is a socket.

Contact Adhesive
Adhesive that is applied to both adherends and after a specified open assembly time will instantly develop a bond when a firm but not sustained pressure is applied.

Contact Alignment
Defines the overall radial play which contacts shall have within the insert cavity so as to permit self-alignment of mated contacts. Sometimes referred to as amount of contact float.

Contact Angle (Bonding)
The angle between the bonding lead or wire and the bonding land.

Contact Angle (Soldering)
The angle of a solder fillet that is enclosed between a plane that is tangent to the solder/basis-metal surface and a planethat is tangnet to the solder/air interface.

Contact Area
The area in contact between two conductors, two contacts or a conductor and a contact permitting the flow of electricity. (MIL-STD)

Contact Arrangement
The number, spacing and arrangement of contacts in a connector. (MIL-STD)

Contact Bond Adhesive
Synonym for contact adhesive.

Contact Cavity
A defined hole in the connector insert or housing into which the contact must fit.

Contact Chatter
Connector ohmic discontinuities.

Contact Durability
The number of insertion and withdrawal cycles that a connector must be capable of withstanding while remaining within the performance levels of the applicable specification.

Contact Engaging & Separating Force
1) The force needed to either engage or separate pins and socket contacts when they are in and out of connector inserts. Values are generally established for maximum and minimum forces. Performance acceptance levels vary by specification and/or customer requirements.__2) Force needed to either engage or separate mating contacts. (MIL-STD)

Contact Female
A contact having an engagement end that will accept entry of a pin contact. (MIL-STD) Also called Socket contact

Contact Float
The overall side-play and/or angular displacement of contacts within the insert cavity. (MIL-STD)

Contact Hermaphroditic
A contact design which is a combination pin and socket and which mates with other contacts of the same design. (MIL-STD) Both mating elements are precisely alike at their mating face.

Contact Inspection Hole
A hole in the cylindrical rear portion of contact used to check the depth to which a wire has been inserted.

Contact Length
The distance of travel made by a contact in touch with another during the insertion and removal of a connector.

Contact Male
A contact having an engagement end that enters the socket contact. (MIL-STD) A male type contact, usually designed to mate with a socket or female contact. It is normally connected to the “dead” side of a circuit. Also called Pin Contact

Contact Plating
Metal plating applied to the base contact metal to provide the required contact resistance and/or wear resistance.

Contact Pressure
The force which mating surfaces exert against one another.

Contact Resistance
1) Electrical resistance of a pair of engaged contacts. Resistance may be measured in Ohms or millivolt drop at a specified current over the engaged contacts. (MIL-STD)__2) Measurement of electrical resistance of mated contacts when assembled in a connector under typical service use. Electrical resistance is determined by measuring from the rear of the electrical area of one contact to the rear of the electrical area of the mating contact (excluding both crimps) while carrying a specified test current.

Contact Retainer
A device either on the contact or in the insert to retain the contact in an insert or body. (MIL-STD)

Contact Retention
The axial load in either direction which a contact can withstand without being dislodged from its normal position within an insert or body. (MIL-STD)

Contact Separation Force
The force required to separate a pair of fully mated contacts.

Contact Shoulder
The flanged portion of the contact which limits its travel into the insert.

Contact Size
An assigned number denoting the size of the contact engaging end. (MIL-STD

Contact Spacing
The distance between the centerlines of adjacent contact areas.

Contact Wipe
The distance of travel (electrical engagement) made by one contact with another during its engagement or separation or during mating or unmating of the connector halves. (MIL-STD)

Contacts
The conducting members of a connecting device that are designed to provide a separable through connection in a cable-to-cable, cable-to-box or a box-to-box situation.

Continuity
(1) A continuous path for the flow of current in an electrical circuit. (2) An uninterrupted path for he flow of electrical current in a circuit.

Continuity Check
A test to determine whether electrical current flows continuously throughout the length of a single wire in a cable or center conductor of a cable assembly.

Continuity Testing
A test that shows that the optical path is continuous with no breaks.

Continuous Bend
Reeving of wire rope over sheaves and drums so that it bends in the same direction, as opposed to reverse bend

Continuous Current Rating
The designated RMS alternating or direct current which the connector can carry continuously under specified conditions.

Continuous Operating Temperature
Maximum temperature at which a component will maintain an acceptable lifetime performance, based on accelerated aging prediction

Continuous Vulcanization
Simultaneous extrusion and curing of elastometic wire coating materials.

Continuous wave (CW)
Energy is emitted from a module continuously, rather than in short pulses. CW applications require the laser to be on at all times. Constant output from an optical source that is active but not modulated by a signal.

Contrahelical
Cable spiraling in an opposite direction than the preceding layer within a wire or cable.

Control Cable
A multi-conductor cable made for operation in control or signal circuits.

Controlled environment vault (CEV)
A reinforced vault designed to provide an environmentally stable underground area to house fiber optic transmission equipment and electronics for switching, monitoring, back-up power, remote terminals, etc.

Controlled Impedance Cable
Package of two or more insulated conductors where impedance measurements betweenrespective conductors are kept essentially constant throughout the entire length.

Convection
A conveying, or transference of heat or electricity by moving particles of matter. The transfer of heat by movement of hot air. Often used in conjunction with infrared radiation to reduce the effect of IR shadowing.

Conveyor Rope
Parallel endless wire ropes used to carry material

Coplanarity
The distance between the lowest and highest lead when the connector is laying in its seating place.

Copolene
A dielectric material, composed of polyisobutylene and polystyrene developed as a substitute of polystyrene. However, polyethylene is more commonly used instead of copolene.

Copolymer
A compound resulting from the polymerization of two different monomers.

copolymerization
Polymerization in which a copolymer is formed. (IUPAC)

Copper
The most widely used electrical conductor in wires and cables. Some of the common types of electrical coppers and copper alloys are:

Copper and Copper Alloys
The most widely used electrical conductor in wires and cables. Copper and its alloys are used extensively for contacts and connectors. Copper has the best conductivity of the common (non-precious) metals. Copper and copper alloys offer excellent corrosion resistance, thigh thermal conductivity and ease of fabrication, joining and forming.

Copper Clad
Steel with a coating of copper welded to it before drawing as opposed to copper-plated. Synonymous with Copperweld.

Copper-Covered Steel Wire
A wire having a steel core and an outer covering of copper.

Copperweld
Copper covered steel wire. Copper and steel welded together. The trade name of Flexo Wire Division (Copperweld Steel Corp.) for their copper-clad steel conductors.

Cord
A small, flexible insulated cable.

Cord Set
Portable cords fitted with a wiring device at one or both ends

Cord, Telecommunications
A cable using stranded conductors for flexibility as in distribution cords or line cords. Line cords can also use tinsel conductors.

Cordage
Tight buffered breakout cables used to build patch cords (jumpers). Internally, the fibers are normally one or two 900-micron coated fibers. The term “zipcord” describes a two-fiber cordage to allow two separate plugs to have their own strain relief.

Cords
A short length of copper wire or fiber optic cable with connectors on each end. Used to connect equipment to cabling, or to connect cabling segments (cross-connection).

Cordset
Portable cords fitted with a wiring device at one or both ends.

Core
(1) In cables, a term used to express a component or assembly of components over which other materials are applied, such as additional components, shield, sheath, or armor; (2) In fiber optics, the transparent glass or plastic section with a high refractive index through which the light travels by internal reflections.

Core concentricity
A measure of the relationship between the geometric center of the core of an optical fiber and the geometric center of the cladding, or how centered the core is.

Core Ellipticity
Measure of the nonroundness of the core.

Core ovality
A ratio of the minimum to maximum diameters of the core within an optical fiber, or how round the core is.

Coring Line
Wire rope used to operate the coring tool for taking core samples during the drilling of a well

Corona
1)A discharge resulting from a partial electrical breakdown in voltage exceeding a certain breakdown value.__2)A discharge due to ionization of air around a conductor due to a potential gradient exceeding a certain critical value.

Corona Extinction Voltage (CEV)
The voltage below which previously initiated corona pulses cease.

Corona Resistance
The time that the insulation will withstand a specified level of field-intensified ionization that does not result in the immediate complete breakdown of the insulation.

Corrosion
1)The destruction of the surface of a metal by chemical reaction.__2)The deterioration of a material by chemical reaction or galvanic action.

Coulomb (C)
A quantity of electricity transferred by a current of one ampere in one second.

Counterpoise
Bare copper, usually soft drawn, buried around the perimeter of a structure for grounding purposes. When grounding electrical transmission towers - usually running parallel to the overhead lines along the right-of-way. A grounding installation employed wh

Coupler
An optical device that splits or combines light from more than one fiber.

Coupling
The transfer of energy between two or more cables or components of a circuit.

Coupling Agent
A substance having functional groups that are capable of reacting with the surfaces of two different substances, thereby chemically bridging them.

Coupling Efficiency
Efficiency of optical power transfer between two components.

Coupling Loss
In fiber optics, signal losses due to small differences in numerical aperature, core diameter, core concentricity and tolerances in splicing connectors when two fibers are aligned. Also known as Splicing Loss and Transfer Loss.

Coupling Nut
That portion of a plug which aids in the mating or unmating of a plug and receptacle and holds the plug to the receptacle. (MIL-STD) Also called Coupling Ring

Coupling ratio
A measure of how a device distributes light from its inputs to its outputs. Expressed as either a percentage or in dB.

Coupling Ring
A device used on cylindrical connectors to lock plug and receptacle together.

Coupling Self-Locking
A device on a plug connector which contains means to automatically secure the coupling to the receptacle and prevent any coupling rotation during shock and vibration. (MIL-STD)

Coupling Torque
The force required to rotate a coupling ring or jackscrew to fully engage a mating pair of connectors.

Covalent Bond
A shared pair of electrons between two atoms

Cover Electrical Connector
An item which is specifically designed to cover the mating end of a connector for mechanical and/or environmental protection. (MIL-STD)

Coverage
The calculated percentage which defines the completeness with which a metal braid covers the underlying surface. The higher percentage of coverage, the greater the protection against external interference .

Covering
Textile braid or jacket of rubber plastics, or other materials applied over wire and cable to provide mechanical protection and identification.

Crazing
The formation of fissures or voids in the adhesive film due to excessive shrinkage characteristics of the adhesive.

Creep
In an adhesive, the time-dependent deformation usually resulting from sustained stress. Final configuration of a terminal barrel formed by the compression of terminal barrel and wire.

Creep Distance
The shortest distance on the surface of an insulator separating two electrically conductive surfaces. (MIL-STD)

Creep Strain
The total strain, at any given time, produced by the applied stress during a creep test.

Creepage
The conduction of electricity across the surface of a dielectric.

Creepage Path
The path electricity must travel across the surface of a dielectric between two conductors. Lengthening the creepage path reduces the possibility of arc damage or tracking.

Creepage Surface
An insulating surface which provides physical separation as a form of insulation between two electrical conductors of different potential.

Crimp
The act of compressing a connector barrel around a cable in order to make an electrical connection.

Crimp Contact
A contact whose back portion is a hollow cylinder to allow it to accept a wire. After a bared wire is inserted, a swedging tool is applied to crimp the contact metal firmly against the wire.

Crimp Height
A measurement taken of the overal wire barrel height after the terminal has been crimped.

Crimp Sleeve
A sleeve of lightweight metal is deformed by compression to encapsulate material and provide strain relief at the rear of a fiber optic plug.

Crimp Termination
Connection in which a metal sleeve is secured to a conductor by mechanically crimping the sleeve with pliers, presses or automated crimping machines.

Crimper
That part of the crimping die, usually the moving part, which indents or compresses the terminal barrels. Sometimes called an indentor.

Crimping
A pressure method of mechanically securing a terminal, splice or contact to a conductor. (MIL-STD) Crimp vs Solder

Crimping Chamber
Area of a crimping tool formed by mating the anvil (nest) and crimper (indentor), in which a contact or terminal is crimped.

Crimping Dies
Portion of the crimping tool that shapes the crimp. (MIL-STD) This term is used to identify the shaping tools that when moved toward each other, produce a certain desirable shape to the barrel of the terminal or contact that has been placed between them. Crimping dies are often referred to as die sets or as die inserts.

Crimping Termination
Connection in which a metal sleeve is secured to a conductor by mechanically crimping the sleeve with pliers, presses or crimp dies.

Crimping Tool
Mechanism used for crimping. (MIL-STD) The term commonly used to identify a handheld mechanical device or table press that is used to crimp a contact, ferrule, terminal or splice.

Critical Angle
Smallest angle at which a meridional ray may be totally reflected within a fiber at the core-cladding interface.

Critical Diameter
Diameter of the smallest bend for a given wire rope which permits the wires and strands to adjust themselves by relative movement while remaining in their normal position

Cross Color
Spurious color patterns in a color picture resulting from incomplete separation of the luminance and chroma portions of the color video signal.

Cross Connect
SYSTIMAX� SCS component where communication circuits are administered (that is, added or rearranged using jumper wire or patch cords). In 110 Connector Systems, Hook-Up Wire or patch cords are used to make circuit connections. In fiber optic connector systems, fiber optic patch cords are used. The cross connect is located in an equipment room or telecommunications closet. See also Jumper Wire and Patch Cord.

Cross Connect Field
Copper wire or fiber terminations grouped to provide cross-connect capability. The groups are identified by color-coded sections of back boards mounted on the wall in equipment rooms or telecommunications closets, or by designation strips or labels placed on the wiring block or unit. The color coding identifies the type of circuit that terminates at the field.

Cross Luminance
A defect that manifests itself as a dot pattern that moves through the picture because of chroma information leaking into the luminance signal.

Cross Sectional Area of a Conductor
The summation of all cross-sectional areas of the individual strands in the conductor, expressed in square inches or more commonly in circular mils.

Cross Sectioning and Analysis Service
Fiber Optic Center's unique cross-sectioning service to identify and isolate problems related to fiber optic terminations that would otherwise be invisible.

Cross Talk
A magnetic or electrostatic coupling which causes the unwanted transfer of energy from one signal path (disturbing circuit) to another signal path (disturbed circuit).

Cross-Connect
A facility enabling the termination of cable elements and their interconnection, and/or cross-connection, primarily by means of a patch cord or jumper.

Cross-Connection
A connection scheme between cabling runs, subsystems and equipment using patch cords or jumpers that attach to connecting hardware on each end.

Cross-over concentration
The concentration at which the sum of the volumes of the domains occupied by the solute molecules or particles in solution is approximately equal to the total volume of that solution. (IUPAC)

Cross-phase modulation (XPM)
A nonlinear optical effect where one wavelength of light affects the phase of a similar wavelength of light.

Cross-Sectional Area
The area of the cut surface of an object cut at right angles to the length of the object.

Crossband
A veneer oriented at right angles to a face veneer used to ensure dimensional stability in a plywood panel

Crosslink
To form chemical bonds between molecules to produce a three-dimensional network; a constitutional unit connecting two parts of a macromolecule that were earlier separate molecules. Note a network may be thought to consist of many "primary chains" that are interconnected by a number of crosslinks. In the vast majority of cases, the crosslink is a covalent bond but the term is also used to describe sites of weaker chemical interactions, portions of crystallites, and even physical entanglements. (IUPAC)

Crosslinked
A term denoting intermolecular bonds between long chain thermoplastic polymers, effected by chemical or irradiation techniques.

Crosslinking
The generation of chemical links between the molecular chains, usually achieved by chemical reactions or high energy irradiation of the material.

Crosslinking by Irradiation
A method of crosslinking polymers that makes a nonflowing material. This generally improves the properties of the polymer.

Crosstalk
An electromagnetic coupling between two physically isolated circuits in a system.  1) A type of interference caused by signals from one circuit being coupled into adjacent circuits.  2) A magnetic or electrostatic coupling which causes the unwanted transfer of energy from one circuit (disturbing circuit) to another circuit (disturbed circuit).

Crush resistance
A test that determines the ability of a fiber optic cable to mechanically and optically withstand the effects of a compressive force. Testing specifies the changes in optical transmittance or attenuation during compressive loading. Specified in the TIA/EIA 455-41 “Compressive Loading Resistance of Fiber Optic Cables” fiber optic test procedure.

Cryogenic
Use of cables in very low temperature environments.

Crystalline polymer
Polymer with a regular order or pattern of molecular arrangement and a sharp melting point.

Cubic Capacity
The most important commerical measurement when the cargo is so lightweight that the ship is filled to capacity without being loaded to the load line (freeboard). Capacity is measured in cubic metres or cubic feet (cu.ft.).

Cure
To change the physical properties of a material by chemical reaction, by the action of heat and catalysts, alone or in combination, with or without pressure. The process by which a compound attains its intended performance properties by means of evaporation, chemical reaction, heat, radiation, or combinations thereof.

Cure Cycle
The period of time that a glue line is being cured in radio frequency.

Cure Speed
Time needed for an adhesive to reach full strength.

Cure Time
The period of time required to attain a full cure.

Curing Agent
A substance or mixture of substances that controls a curing reaction.

Curing Cycle
The time, temperature, and pressure required for curing.

Curing Oven
An oven specifically manufactured to use thermal curing to harden the epoxy injected into a fiber-optic ferrules.

Curing Temperature
The temperature to which an adhesive or an assembly is subjected to cure the adhesive.

Curing Time
The time needed to cure or “set” an adhesive.

Curl
The degree to which a wire tends to form a circle after removal from a spool. An indication of the ability of the wire to be wrapped around posts in long runs.

Current
The rate of transfer of electricity. The practical unit is the ampere, which represents the transfer of one coulomb per second.

Current Carring Capacity
1)The current a conductor of a given size is capable of carrying without exceeding its temperature limitation.   2)The maximum current an insulted conductor can safely carry without exceeding its insulation and jacket temperature limitations. (Same as Ampacity)

Current Penetration
The depth a current of a given frequency will penetrate into the surface of a conductor carrying the current

Current Probe
A sensor which measures EMI and clamps onto a wire, wire pair, coaxial line or cable harness to help locate and quantify ground loops. Snap-on current probes measure the normal-mode current in a wire pair, coaxial line or wire bundle.

Current Rating
The maximum continuous electrical flow of current recommended for a given wire in a given situation. Expressed in amperes (AMPS).

Current-Carrying Capacity
The maximum current an insulated conductor or cable can continuously carry without exceeding its temperature rating. It is also called ampacity.

Current, Alternating (AC)
An electric current that periodically reverses direction of electron flow. The number of full cycles occurring in a given unit of time (one second) is called the frequency of the current.

Current, Direct (DC)
Electrical current whose electrons flow in one direction only; it may be constant or pulsating as long as their movement is in the same direction.

Customer Premises
Building(s) with grounds and appurtenances (belongings) under the control of the customer.

Customer Premises Equipment (CPE)
Customer owned equipment used to terminate or process information from the public network e.g. Multiplexed or PABX.

Cut Off Frequency
The frequency, above which other than the TEM mode may occur. The transmission characteristics of cables above their cutoff frequency may be unstable.

Cut Off Tab
The small tabs that remain on the front and back of a terminal after is has been applied.

Cut off wavelength
For a single mode fiber, the wavelength above which the fiber exhibits single mode operation.

Cut Through Resistance
The ability of a material to withstand mechanical pressure, (usually a sharp edge or small radius) without separation.

Cut-Down
A method of securing a wire to a wiring terminal. The insulated wire is placed in the terminal groove and pushed down with a special tool. As the wire is seated, the terminal cuts through the insulation to make an electrical connection, and the spring-loaded blade of the tool trims the wire flush with the terminal. Also called punch-down.

Cut-Off
The frequency above which a coaxial device will support electrical modes other than the principal TEM (transverse electromagnetic) mode. This sets an upper limit to the coaxial line’s normal useful frequency range, distorting pulses and modulation envelopes.

Cut-Through Resistance
The ability of a material to withstand mechanical pressure, usually a sharp edge of prescribed radius, without separation.

Cutback method
A technique for measuring fiber attenuation by performing two transmission measurements. One is done at the output end of the full length of the fiber. The other is usually done within 1-3 meters of the input end and accessed by “cutting back” the test fiber and measuring the change in the pre- and post-cutback measurements.

Cutoff wavelength
That wavelength greater than which a particular waveguide mode ceases to be a bound mode. When transmitting lower than a single-mode fiber’s cutoff wavelength, the fiber transmits multimode. For G.652 single-mode fibers the cutoff wavelength is 1260 nm. For G.655 fibers, it can range from 1260 nm to 1450 nm.

Cutout Connector
The hole, usually round or rectangular, cut in a metal panel for mounting a connector. May include holes for mounting screws or bolts. (MIL-STD)

Cyanoacrylate Adhesive
Group of adhesives which show "instant" cure properties and bond to a wide variety of substrates. Cure is by contact with alkaline materials. Weakly alkaline materials such as water, cause the cure to start. Commonly referred to as "super glue."

Cycle
One complete sequence of values of an alternating quantity, including a rise to maximum in one direction and return to zero; a rise to maximum in the opposite direction and return to zero. The number of cycles occurring in one second in called the frequency.

Cycle Life
The number of repetitive flex motions that a wire or cable can withstand prior to breakdown.

Cyclic Redundancy Check (CRC)
A coded sequence of information allowing error checking and correction.

Cylindrical Drum
Hoisting drum of uniform diameter

D TYPE
A description for the 9, 15 and 25 pin connectors widely used for data communications and microcomputer peripherals. It looks very loosely like a "D" when viewed vertically.

D-1 Format
A serial digital recording format.

D-2 Format
A composite digital recording format.

D-3 Format
A composite digital recording format.

D-Block Carrier
A 10-MHz personal-communications-services carrier serving a basic trading area in the 1865-to-1870-MHz band paired with the 1945-to-1950-MHz band.

D-CHANNEL
Delta/Data Channel. A sort of status line in the ISDN arena. A 16 Kbps line carrying control signals and call data in the BRI interface. A 64 Kbps line in the PRI interface.

Daisy Chain
Connections in series that render all of the connections common.

Dark fiber
An unused fiber installed for future use.

Data communications
The transmission of data from one point to another.

Data communications equipment (DCE)
A device, typically a modem, used in RS-232 data networks.

Data compression
A mathematical technique that encodes data so that it uses less space (bandwidth) during transmission or storage.

Data encryption
A mathematical technique that encodes data so that it is more secure during transmission or storage. The data must be decrypted for use.

Data Grade Circuit
A telephone line capable of carrying high-speed data. The line is specially conditioned to accommodate this.

Data Link
1) The physical means of connection one location to another for the purpose of transmitting and receiving data.  2) Synonymous with communication link.

Data Link Layer
Layer 2 of the Open Systems Interconnect (OSI) model; it defines protocols governing data packetizing and transmission into and out of each node.

Data Service Unit
DSU. A device for transmitting data on digital transmission facilities. Sometimes incorporated with a CSU.

Data Set
Another term for modem.

Data terminal equipment (DTE)
Used with RS-232 data equipment, DTE is a specific pinout configuration on standard RS-232 DB9 or DB25 connectors. Usually a DTE device is a terminal with a male connector; its complementary device (DCE) normally has a female connector.

Data Transmission
The conveying of data from one place for reception elsewhere by signals transmitted over a data circuit.

dB
(1) Abbreviation for decibel; (2) The loss of a signal in a conductor expressed in decibels, denoting the ratio of the power input to output; (3) One tenth of a bel.

dB Loss
The loss of a signal in a conductor expressed in decibels.

dB/km
A logarithmic unit describing the ratio of loss of power per kilometer distance. These values are always referenced to a specific wavelength, e.g., 0.35 dB/km at 1310 nm, and are used by fiber and cable manufacturers to define the optical fiber’s attenuation.

DB15
A standardized connector with 15 pins for Ethernet transceivers.

DB25
A standardized connector with 25 pins for parallel or serial connections.

DB9
A standardized connector with nine pins for token ring and serial connections.

dBc
Decibel Carrier

dBd
Decibel Dipole

dBi
Decibel Isotropic

dBm
Decibels relative to one milliwatt. A positive number indicates the power is above one milliwatt; a negative number indicates the power is below. This unit has become common in fiber optic communication systems because the power of light sources used with optical fibers is on the order of one milliwatt.

DC
Direct current. Current which moves in a single direction in a steady flow. Normal household electricity is alternating current (AC) which repeatedly reverses its direction. However, many electronics devices require DC, and therefore must convert the current into DC before using it.

DC Resistance
Provides an effective check on cable and connector integrity. Both cabling and connectors have inherent DC resistance. Loop resistance is the combined resistance of each individual wire in a two-wire pair. It is tested for each pair by placing a known DC voltage on one wire in the pair, shorting the Remote Handset and reading the voltage loss at the Display Handset. DC loop resistance testing is essential to isolating poor connector punch downs, cable damage and shorts.

DCS-1800
1) Digital Cordless Standard 1800. 2) Digital Communications Service 1800 MHz is an upbanded variant of the Global System for Mobile Communications.

Dead Face
The term which describes the various methods used to protect contacts when not engaged.

Dead Front
Mating surfaces of a connector designed so that the contacts are recessed below the surface of the connector insulator body to prevent accidental short-circuiting of the contacts.

Deadweight
The largest weight of cargo, bunkers and stores a ship is able to carry. Expressed in metric tons (1000 kg) or long tons (1016 kg). The deadweight tonnage is the most important commerical measurement. Normally the maximum payload for a ship is three to ten percent lower than the deadweight, due to the weight of bunkers and stores, etc.

Deadzone
An area where an OTDR cannot make measurements. It is limited by the laser’s pulse width, the reflection of the front panel connector, and detector circuitry. The shorter the pulse width, the shorter the deadzone.

Deadzone box
A package with internal fiber that is used to test fiber spans with an OTDR, allowing attenuation and connector reflectance to be measured within the OTDR’s dead zone. The internal fiber must be at least 20 times the OTDR’s minimum pulse width, and they are most commonly sold in lengths of 500 or 1,000 meters.

Deceleration Stress
Additional stress imposed on a wire rope due to decreasing the velocity of the load

Decibel (dB)
1)A unit of measurement to express logarithmic differences of power level. It is used to express power gain in amplifiers or power loss in passive circuits or components. Expressed as dB.  2)A unit to express differences of power level. A term that expresses two power levels used to indicate gains or losses in a system.

Decibel/kilometer (dB/km)
A unit of measurement for fiber optic attenuation.

Decoder
1) A device used to separate the individual component portions of a composite signal.  2) A device the decodes scrambled television broadcast signals.

Defect
Any non-conformance with the normally accepted characteristics of a part.

Degradation
A gradual deterioration in performance.

degree of polymerization
the number of monomeric units in a macromolecule or oligomer molecule. (IUPAC)

Delamination
The separation of layers in a laminate because of failure of the adhesive, either in the adhesive itself or at the interface between the adhesive and the adherend.

Delay Line
1) A device used to delay a signal for a specified length of time. 2) A cable made to provide very low velocity of propagation with long electrical delay for transmitted signals.

Delay Skew
The difference in propagation delay between any two pairs within the same cable sheath. Also known as Propagation Delay/Delay Skew. Delay Skew is a measurement of the signaling delay difference from the fastest pair to the slowest. Delay Skew is calculated from Propagation Delay measurements.

Delayed Strain
See latent strain.

Demarcation point
The point of interconnection between telephone company terminal equipment and a building’s wiring where the operational control or ownership changes.

Demodulation
The process of separating the information signal from the carrier signal.

Demultiplexer (Demux)
A device that separates the two or more signals that have been combined into a multiplexed signal. An optical demultiplexer separates signals at different wavelengths. An electronic demultiplexer separates signals that have been electronically multiplexed by time (TDM) or frequency (FDM).

Denier
Unit of measure for the linear mass density of fibers. It is defined as the mass in grams per 9000 meters.

Dense wavelength division multiplexing (DWDM)
A method of increasing the amount of data that can be transmitted over an optical fiber.

Density
Ratio of weight (mass) to volume of a material – ie grams per cubic centimeter or pounds per gallon.

Depolarization of scatter light
The phenomenon, due primarily to the anisotropy of the polarizability of the scattering medium, resulting from the fact that the electric vectors of the incident and scattered beams are not coplanar and that, therefore, light scattered from a vertically (horizontally) polarized incident beam contains a horizontal (vertical) component. (IUPAC)

Depolymerization
Separation of a complex molecule into simple molecules; also softening of a sealant by the same action.

Depressed-clad optical fiber
The inner cladding, next to the core, has a lower index of refraction than the outer cladding region. Depressed refers to the IR mismatch between the two claddings, resulting in a small MFD that reportedly fusion splices more readily but tends to be more sensitive to the bending losses encountered in most enclosures.

Depth of Crimp
Thickness of the crimped portion of a connector measured between two opposite points on the crimped surface. The distance the indentor penetrates into the barrel. (MIL-STD)

Derating Factor
A factor used to reduce the current carrying capacity of a wire when used in environments other than that for which the value was established.

Design Factor
In a wire, the ratio of the minimum break strength to the total working load. Typical ratio is 5:1, but standards vary based upon industry, environment, and application

Destructive Test
See test, destructive.

Detector
A device that picks up light from fiber and converts the information into an electrical signal. A device such a photodiode or photodetector that converts optical energy into electrical energy. They can be made from silicon, germanium, gallium arsenide, indium gallium arsenide or from other semiconductors, depending on the wavelengths to detect. The positive-intrinsic-negative (PIN) and the avalanche photodiode (APD) types are used in fiber optics. PIN types can be used for analog or digital systems, while APDs with their internal amplification can only be used in digital systems.

Detector-amplifier
A device in which an optical detector is packaged with electronic amplification circuitry.

Device-Under-Test (DUT)
The cable, harness, or other assembly that is being tested by the cable tester.

Device, As Related to a Work Station
An item such as a telephone, personal computer, or graphic or video terminal.

Device, As Related to Protection
A protector, a protector mount, a protector unit or a protectomodule.

Dewetting
A situation where a lead was at one point in the soldering process wetted by the solder, but due to extended time or temperature, the presence of intermetallics, volatiles or other causes, has become withdrawn from the wetted surface.

Dextrin
A water based product derived from the acidification and/or roasting of starch.

DIACID
A molecule with two carboxylic acid (-COOH) functional groups

Diameter
Distance measured across the center of a circle circumscribing the wires of a strand or the strands of a wire rope

DIAMINE
A molecule with two amine (-NH2) functional group

Diamond Lapping Film
Diamond lapping films cut and polish the hard ceramic ferrules and the softer fibers close to the same rate, easily controlling fiber undercut or protrusion. Diamond also helps assure the ferrule geometries meet the Telcordia GR 326 version 3 specifications, and leave the ferrule in a condition ready for the final polish film. Diamond is always recommended for the intermediate steps of machine polishing of single mode or multimode ceramic connectors, and for single mode hand polishing of ceramic connectors. When stopping at a diamond of 1um or less, a good surface finish results with great geometries, but with a return loss of -35 dB at best. If back reflection of -55 dB or better is required, see our Final Polish Films.

Die Closure
The gap between indenter dies at full handle closure. Usually defined by Go/No-Go dimensions.

Dielectric
A nonconducting or insulating material that resists passage of electric current.  1) A material having electrical insulating properties. (MIL-STD)  2) Any insulating material between two conductors which permits electrostatic attraction and repulsion to take place across it.  3) A non-conducting material or a material having the property that the energy required to establish an electric field is recoverable, in whole or in part, as electric energy. A vacuum is a dielectric.

Dielectric Breakdown (DWV)
The voltage required to cause an electrical failure or breakthrough of the insulation. The insulation barrier is insufficient and only a small air gap keeps metal conductors from shorting. When high voltage is applied, the tester detects the weak insulation through an electrical arc (electricity flowing through the insulation).

Dielectric Cable
A nonconducting cable, such as fiber optic cable, without metallic members.

Dielectric Constant
Also called permittivity. That property of a dielectric which determines the amount of electrostatic energy that can be stored by the material when a given voltage is applied to it. Actually, the ratio of the capacitance of a capacitor using the dielectric to the capacitance of an identical capacitor using a vacuum as a dielectric.

Dielectric Constant (K)
The ratio of the capacitance of a condenser with dielectric between the electrodes to the capacitance when air is between the electrodes. Also called Permittivity and Specific Inductive Capacity (SIC).

Dielectric Constant (Permittivity)
1)The ratio of the capacitance using the material in question as the dielectric, to the capacitance resulting when the material is replaced by air.  2)That property of a dielectric which determines the electrostatic energy stored per unit volume for a unit potential gradient. The ratio of the capacitance using the material in question as the dielectric, to the capacitance resulting when the material is replaced by air. The dielectric constant is the most important design parameter for coaxial cables and determines dimensions, losses and propagation characteristics.

Dielectric Curing
The use of a high frequency electric field through a joint to cure a synthetic thermosetting adhesive; a curing process for wood and other nonconductive joint materials.

Dielectric Heating
The heating of an insulating material when placed in a radio-frequency field, caused by internal losses during the rapid polarization reversal of molecules in the material.

Dielectric Loss
Power dissipated in an insulating medium as the result of the friction caused by molecular motion when an AC Electric field is applied. In a coaxial cable, the losses caused by the transformation of electromagnetic energy into heat within the dielectric material.

Dielectric Loss Factor (Dielectric Loss Index)
A measure of the loss characteristics of a dielectric material.

Dielectric Strength
1)The voltage which an insulation can withstand before breakdown occurs. Usually expressed as a voltage gradient (such as volts per mil).  2)The maximum voltage that a dielectric material can withstand, under specified conditions. without rupturing. Usually expressed as a voltage gradient such as volts per mil.

Dielectric Test
A test in which a voltage higher than the rated voltage is applied for a specified time to determine the adequacy of the insulation under normal conditions. Sometimes called a "Hi-Pot" test (high potential).

Dielectric Withstanding Voltage
The maximum potential gradient that a dielectric material can withstand without failure.

Differential group delay (DGD)
A delay caused by different arrival times of optical signals, which results in modal dispersion. In multimode fibers, DGD is the delay difference of the various modes. In single-mode fibers, DGD is the delay caused by chromatic, waveguide, and polarization mode dispersion.

Diffraction
Phenomenon that results when light passes by an opaque edge or through an opening, generating weaker secondary wavefronts. These secondary wavefronts interfere with the primary wavefronts as well as with each other to form various patterns.

Diffraction Grating
An array of fine, parallel, equally-spaced reflecting or transmitting lines that mutually enhance the effects of diffraction to concentrate the diffracted light in a few directions determined by the spacing of the lines and by the wavelength of the light.

Digital
(1) Pertaining to the utilization of discreet integral numbers in a given base to represent all the quantities that occur in a problem or a calculation. It is possible to express in digital form all information stores, transferred or processed by a dual-state condition; e.g., on-off, open-closed and true-false. (2) Compare with analog.

Digital Advanced Mobile Phone System (DAMPS)
Digitally-enhanced AMPS based on the ID-54 standard. Also referred to as TDMA.

Digital Cordless Telephone US (DCTU)
A version of Digital European Cordless Telecommunications proposed for the US personal-communications-services market.

Digital European Cordless Telecommunications (DECT)
DECT is a digital cordless telecommunications system initially intended for wireless-public-branch-exchange applications, but which may also be used in the consumer market. DECT supports voice and data communications

Digital signal (DS)
A hierarchy of digital signal speeds used to classify capacities of digital lines and trunks. The fundamental speed level is DS-0 (64 kb/s). A signal that represents information by a series of fixed, encoded, rectangular pulses, usually consisting of two possible voltage levels. Each voltage level indicates one of tow possible values or logic states, such as on or off, open or closed, true or false. See also Analogue Signal.

Digital Signal Processor (DSP)
A microprocessor that digitizes analog signals.

Digital subscriber line (DSL)
A generic name for a family of digital lines provided by local telephone companies to their subscribers.

Digital transmission
A technique in which all information is converted into binary digits for transmission (string of discrete "on-off" or "high-low" pulses).

Digital video
Video signals represented by discrete numerical values rather than by continuously varying signal levels as in analog video. Because of this, it is simpler to maintain the fidelity of the video information as it travels through a transmission medium.

Digitize
The conversion of an analog or continuous signal into a data stream of binary digits.

Diluent
An ingredient usually added to an adhesive to reduce the concentration of bonding materials.

Dilute solution
A solution in which the sum of the volumes of the domains occupied by the solute molecules or particles is substantially less than the total volume of the solution. (IUPAC)

Dimer
Two monomers linked together. A polymer containing two monomers.

DIN 7/16
Coaxial connector interface with screw type coupling mechanism. Larger than N interface and suitable for medium to high power applications. Frequency range is DC - 7.5 GHz.

Diode
An electronic device that restricts current flow chiefly to one direction. 

Diode adapter receptacle
Designed to house LED or PIN/APD diodes in a receptacle that allows the mating plug to position the fiber for an optimum coupling efficiency.

Dip Coating
An insulating coating applied to the conductor by passing the conductor through an applicator containing liquid insulating medium.

Dip Solder Terminal
The terminals on a connector which are inserted into holes in a PC board and then soldered into position.

Diplexer
A component used to provide two functions, such as multiplexing or filtering optical signals. For example, a diplexer used at an FTTx optical network terminal filters the downstream 1490-nm wavelength and multiplexes the upstream 1310-nm wavelength to or from a single fiber.

Dipole Antenna
Antenna with the gain, pattern and impedance defined at and near resonance of one-half wavelength. This antenna is split at its electrical center for connection to a transmission line. The radiation pattern is maximum at right angles to the axis of the antenna.

Direct Burial Cable
A cable installed directly in the earth.

Direct Buried
See buried.

Direct Capacitance
The capacitance measured directly from conductor to conductor through a single insulating layer.

Direct Current (DC)
An electric current that flows in only one direction, substantially constant in value.

Direct Current Resistance (DCR)
The resistance offered by any circuit to the flow of direct current.

Direction of Lay
The lateral direction in which the strands of a conductor run over the top of the cable conductor as they recede from an observer looking along the axis of the conductor or cable. Also applies to twisted cable.

Directional Antenna
An antenna which transmits or receives in certain directions more effectively than others.

Directional Coupler
A fiber optic coupler that preferentially transmits light in one direction.

Directionality
A quantification of how much light is passing in any direction, measured in dB. If a 0 dBm signal passes through a coupler with 50 dB directionality, only –50 dB (0.01 ?m) will pass in the wrong direction.

Directly-modulated laser (DML)
A laser directly modulated by electrical voltage and current.

Disconnect
A reusable conductive device designed to be separated from its mated part.

Discontinuity
1) A broken connection or the loss of a specific connection characteristic.  2) The temporary interruption or variation in current or voltage.

Discrete Wiring
Wire or wires having distinct identity and purpose.

Discruptive Discharge
A sudden, large increase in current through an insulation medium due to the complete failure of the medium under the electrostatic stress.

Dispersion
In fiber optics, the variation of the refractive index of a material with wavelength, causing light of different wavelengths to travel at different velocities in the material.

Dispersion compensation module (DCM)
Dispersion compensation modules use a chirped fiber Bragg gratings (FBG) and a optical circulator, which act as an individual wavelength or channel filter. Faster wavelengths are reflected further in the filter than slower wavelengths, enabling the slower wavelengths to catch up to the faster ones. The amount of delay is determined by the physical characteristics of the FBG. DCMs typically have insertion losses around 5 dB, consisting only of circulator and reflection losses. Tunable versions are also available.

Dispersion-compensating fiber (DCF)
A type of specialized fiber designed to offset or compensate for chromatic dispersion in single-mode fibers.

Dispersion-shifted fiber (DSF)
Specified by ITU-T G.653, this fiber provides low attenuation and dispersion at 1550 nm. It could not be used with DWDM as it caused four wave mixing, and has been obsoleted and replaced by G.655 nonzero dispersion-shifted (NZDS) fiber.

Disruptive Discharge
A sudden, large increase in current through an insulation medium due to the complete failure of the medium under the electrostatic stress.

Dissipation
Unusable or lost energy, such as the production of unused heat in a circuit.

Dissipation Factor
The tangent of the loss angle of the insulating material. (Also referred to as loss tangent, tand and approximate power factor.)

Dissipation Factor (Loss Tangent)
A measure of the loss characteristics of a dielectric material

Distortion
An unwanted change or addition to a signal or waveform when it is amplified. This definition excludes noise which is an extraneous signal superimposed on the desired signal.

Distributed feedback (DFB) laser
A laser that uses an internal grating to reduce the line width of the laser, and may be used for analog applications, e.g., AM/FM/DWDM.

Distributed Processing
A system or network whereby the processing is done at each individual workstation and not at a central device. A LAN is an example of distributed processing.

Distribution Cable
In telecommunications and CATV systems, the transmission cable between the distribution amplifier and the drop wire . A tight-buffered non breakout style cable mostly used for indoor installations. Jackets can be plenum, riser, or low smoke zero halogen to meet building codes. Internally, the fibers have a 900-micron coating. In the outside plant, the term “distribution cable” is used by service providers to describe the cable between the feeder (backbone) and drop cables.

Distribution Frame
A structure with terminations for connecting the permanent cabling of a facility in such a manner that interconnection or cross-connections may be readily made.

Distribution Panel
A combination of a patch panel and splice panel.

Distributor
The term used for the functions of a collection of components (for example, patch panels, patch cords) used to connect cables.

Disturbed Conductor
A conductor that receives energy generated by the field of another conductor or an external source such as a transformer.

Doctor Bar
Device that controls the amount of adhesive applied.

Doctor Blade
A scraper mechanism that regulates the dimensional thickness of adhesive on the spreader rolls or on the surface being coated. (Synonyms: doctor knife; doctor bar.)

Doctor Roll
A revolving roller mechanism resulting in a wiping action for regulating the adhesive supplied to the spreader roll.

Dog-Leg
Permanent short bend or kink in a wire rope caused by improper use

Domain
An area including all peripherals and nodes under control of a single computer or server in a network.

Domains
sequences or regions in block copolymers.

Domestic Wire Rope
Wire rope that is stranded and closed in the United States of America

Domstat
Domestic communications satellite

Dopant
A material, usually germanium or boron oxide, added to silica to change its index of refraction.

Doping
Controlled addition of small quantities of an impurity to a pure substance in order to change its characteristics, e.g., increase the refractive index of the fiber core.

DOS
Disk Operating System

Dot Coding
Process of tool imprinting a 22-10 AWG PIDG terminal. Sot coding indicates whether the proper tool has been used.

Double Bond
Two covalent bonds (two shared pairs of electrons between two atoms) represented by "=" (Examples: C=C, C=O)

Double Crimp
The process of tow or more mechanical crimping operations on the same location in a single terminal.

Double Shield
Two shields, on over the other, used to improve the shield effectiveness.

Double spread adhesive
An application of adhesive to both adherends or as two layers on one adherend.

Double-strand chain
Ladder chain a chain that comprises constitutional units always joined to each other through four atoms, two on each constitutional unit. (IUPAC)

Double-strand copolymer
Ladder copolymer a copolymer, the macromolecules of which are double-strand chains. (IUPAC)

Double-strand polymer
Ladder polymer a polymer, the macromolecules of which are double-strand chains. (IUPAC)

Dowel
A cylindrical pin used to reinforce the strength of an assembly joint.

Downline Impedance
LAN Cable Testers perform this function using a Time Domain Reflectometer (TDR) that samples and analyzes the impedance of a link. Relative Impedance is measured as a function of length and each cable can be viewed in graphical format along its length to ascertain where the anomalies are located, whereas Characteristic Impedance is usually measured in a laboratory with complex test equipment such as an expensive network analyzer. The TDR measures relative impedance in the field to find crimps, kinks and/or stretched cable that would show up as a blips, peaks or valleys on the otherwise flat line graph of a good link. (also see FAULT FIND)

Downlink
The transmission of RF signals from a satellite to an earth station.

Drain Wire
In a cable, an insulated wire laid over the component or components, usually under aluminized Mylar and used for a ground connection.

Draw
A step during the optical fiber manufacturing process in which a consolidated preform is loaded into a high temperature furnace and “drawn down” to the diameter of an optical fiber’s cladding, then cooled.

Draw Feed Stock
Rod or wire that is subsequently drawn to a smaller size.

Drawing
In the manufacturing of wire, pulling the metal through a die or series of dies for reduction of diameter to a specified size.

Driver IC
An amplifier in an integrated circuit that increases signal current to the LED for greater transmission distance.

Drop Cable
A cable connecting a workstation or peripheral to the main network cable.

Drop Ceiling
A ceiling that creates an area or space between the ceiling material and the structure above the material. Synonym: False Ceiling, Suspended Ceiling.

Drop Ship
A process where customers buy the parts and materials and they are shipped to the manufacturer. The manufacturer then builds the products and deliver completed assemblies or cables to the customer. 

Drop Wire
A telephone cable, usually consisting of one insulated telephone pair, which is used to connect a subscribers premises to open wire lines on poles.

Drum
A cylindrical flanged barrel of uniform or tapering diameter on which rope is wound for operation or storage. It may be smooth or grooved

Dry
To change the physical state of an adhesive or a substrate by the loss of solvent constituents by evaporation or absorption, or both.

Dry bond adhesive
Synonym for contact adhesive.

Dry fit
It is when fiber is inserted into a plug’s ferrule or termini to verify the strip length and fit prior to insertion of the bonding adhesive. This helps the technician to recognize the “feel” of the fiber insertion process.

Dry Strength
The strength of an adhesive joint determined immediately after drying under specified conditions or after a period of conditioning in a standard laboratory atmosphere.

Drying agent
A component of a sealant that accelerates the oxidation of oils or unsaturated polymers.

Drying temperature
The temperature to which an adhesive or an assembly is subjected to dry the adhesive.

Drying time
1) The period of time during which an adhesive or an assembly is allowed to dry, with or without the application of heat or pressure, or both; 2) The interval of time between the point of liquid adhesive application to the adherend substrate and the time at which adhesive particle coalescence occurs.

Dual Coaxial Cable
Two individually insulated conductors laid parallel or twisted and placed within an overall shield and sheath.

Dual in-line package (DIP)
Only refers to pigtailed dual in-line packaged devices.

Dual MTJ Testing
Using two MTJs, one at either end of DUT, not necessarily Bir-Directional.

Dual Self-Normal Jack
A jack that provides a connection between the two rear connectors, except when interrupted by the insertion of a video patch plug in either of the two front panel receptacles.

Dual-Fiber Cable
A type of fiber optic cable that has two single-fiber cables enclosed in a jacket of extruded plastic.

Dual-Mode Phone
A phone that operates on analog and digital networks.

Dubbing
Electronic duplicating of recorded audio and/or video signals.

Duct
(1) A single enclosed raceway for wires or cables. Also Conduit, Raceway; (2) a single enclosed raceway for wires or cables usually used in soil or concrete, (3) an enclosure in which air is moved. Generally part of the HVAC system of a building.

Ductile
Capable of being drawn out or hammered thin, or of being flexed or bent without failure.

Ducts
The main feeder channels in which communication cable is routed between buildings in a campus environment. See also Campus Backbone Cable.

DUKPT
Derived Unique Key Per Transaction

Dummy Connector Assembly electrical
Two or more electrical connectors having common mounting or mounted on each other, each one capable of being independently replaced. Excludes items which are furnished as mated pairs or sets. (MIL-STD)

Dummy Connector Plug
A connector device designed to mate with a receptacle connector to perform protective, environmental and/or electrical shorting functions.

Dummy Connector Receptacle
A connector receptacle which does not have provisions for attaching conductors. It is generally used for storage of a cable assembly connector plugs. (MIL-STD)

Dummy Load
A dissipative device used at the end of a transmission line or waveguide to convert transmitted energy into heat, so essentially no energy is radiated outward or reflected back to its source.

Duplex
Referring to a type of data transmission, either half or full. Half duplex permits only one-way communication. Full duplex allows simultaneous two-way transmission.

Duplex Cable
(1) A cable composed of two insulated single conductor cables twisted together. (2) A cable composed of two fibers typically 62.5/125 mm Multi-Mode, placed in parallel under a thermoplastic sheath.

Duplex Parallel
Typically used in the thermocouple industry to denote two parallel conductors of dissimilar metals insulated in parallel without twist and jacketed. Commonly applied to thermocouple grades and extension wires

Duplex Transmission
1) Data transmission over a circuit capable of transmitting in both directions at the same time.  2) Synonymous with full duplex transmission.

Durability
As related to adhesive joints, the endurance of joint strength relative to the required service conditions.

Durometer
A measurement used to denote the hardness of a substance, usually an elastomer.

Dust Cap
A protective cover that fits tightly over the connector ferrule, plug, or sleeve. Usually made of plastic, it is used to keep the connector endface clean.

Dust Cover
An item which is specifically designed to cover the mating end of a connector for mechanical and/or environmental protection. (MIL-STD)

DUT
Device Under Test.

DVB Project
Digital Video Broadcasting Project

DWDM
See DENSE WAVELENGTH DIVISION MULTIPLEXING.

Dwell cycle
The period of time after a panel has been cured in radio frequency, but before pressure is released to allow additional cure and equalizing.

Dynamic range
For an optical instrument, defined (in dB) as the ratio of the smallest signal that can be observed at a specified wavelength separation in the presence of a strong nearly-saturating signal.

E-band
Defined by ITU-T G.692 as “extended” for wavelengths between 1360 and 1460 nm. This band includes the high OH peak in single-mode fibers. G.652D fiber is designed for transmission within the extended band. In FTTx systems, the term can be confused with the enhancement band, which the ITU-T G.983 and G.984 PON FTTx standards define as the wavelengths between 1550 and 1560 nm for RF overlay transmission of video signals.

E-Block Carrier
A 10-MHz personal-communications-services carrier serving a basic trading area in the 1885-to-1890-MHz frequency range paired with 1965-to-1970-MHz

E-business
Electronic Business

E-Netz
German name for GMS 1800 network

E-tailing
Short for “electronic retailing”

E&M Signaling
Originally “Ear” and “Mouth,” now ‘recEive” and “TransMit.”

Earth
British terminology for zero reference ground.

Earth Station
The electronic ground equipment used with a parabolic-shaped antenna or "dish" to process RF signals to and from a satellite.

EBCDIC
Extended Binary Coded Decimal Interchange Code. An 8-bit code developed by IBM for data transfer between their computers.

EBONE
European Backbone

Eccentricity
A measure of the center of a conductor's location with respect to the circular cross-section of the insulation surrounding it, expressed as a percentage of center displacement of one circle within the other.

Eddy Current
An electric current induced in a conductor by a varying magnetic field.

Edge Curl
The peeling back or lifting of the outer edge of a tape after application. (See cupping)

Edge-emitting diode (ELED)
A diode that emits lights from the edge of the semiconductor chip, producing higher power and narrower spectral width.

Efficiency (wire rope)
Percentage ratio of measured breaking strength of a wire rope to the aggregate strength of all individual wires tested separately

Ekonol
A moldable, high temperature polymer.

Elastic Limit
Limit of stress above which a permanent deformation takes place within the material

Elastic Memory
The ability of a crosslinked polymer to be deformed to some predetermined shape, hold that shape for a period, and then return to its original shape upon application of heat.

Elasticity
The ability of a material to return to its original shape after removal of a load.

Elastomer
Type of polymer. A material which at room temperature stretches under low stress to at least twice its length and snaps back to original length upon release of stress.

Electric Strength
The maximum potential gradient that a material can withstand without rupture.

Electrical Length
That length of a cable assembly expressed as degrees of a cycle or fraction of a wave length for the signal transmitted. In the case of a cable assembly, the electrical length equals the physical length times the square root of the dielectric constant.

Electrical Resistance Test
A measurement of the resistance from circuit to circuit through the interfacial connection, designed to insure a satisfactory connection.

Electro-Tinned
Electrolytic process of tinning wire using pure tin.

Electrode
A conductor through which a current enters or leaves a nonmetallic conductor. The device in a fusion splicer that discharges the electric energy, fusing two or more fibers together.

Electrodes
Conductors, usually strips or plates used to carry the radio frequency power to the surfaces of the material to be heated.

Electrolysis
The production of chemical changes by passage of current through an electrolyte.

Electrolytic corrosion factor
A measure of the tape's corrosive effect on a copper conductor. This is particularly important in the selection of tapes for use as electrical insulation.

Electrolytic Tough Pitch
A term describing the method of raw copper preparation to ensure a good physical and electrical grade copper finished product containing less than 1/10 of 1% impurities. (ASTM B5.)

Electromagnetic
Pertaining to the combined electric and magnetic fields associated with movements of electrons through conductors. Describes a devices ability to function properly in athe customer's environment without causig electomagnetic interference to other equipment, or itself being susceptible to external interference.

Electromagnetic Compatibility (EMC)
The capability of equipment or systems to be used in their intended environment within designed efficiency levels without causing or receiving degradation due to unintentional EMI.

Electromagnetic Coupling
The transfer of energy by means of a varying magnetic field. Inductive Coupling.

Electromagnetic Field
A rapidly moving electric field and its associated moving magnetic field.

Electromagnetic Flux
Electric and magnetic fields (commonly referred to as emissions) generated by equipment or system.

Electromagnetic Induction
The production of a voltage in a coil due to a change in the number of magnetic lines of force (flux linkages) passing through the coil.

Electromagnetic Interference (EMI)
A natural or man-made electrical or electromagnetic event conducted or radiated and resulting in unintentional and undesirable responses. Referred to as EMI

Electromagnetic Pulse (EMP)
A burst of electromagnetic radiation that results from an explosion (usually from the detonation of a nuclear weapon) and/or a suddenly fluctuating magnetic field.

Electromotive Force (E.M.F)
Pressure or voltage. The force which causes current to flow in a circuit.

Electron Volt (EV)
A measure of the energy gained by an electron falling through an electric field produced by one volt.

Electronic Industries Alliance (EIA)
Former body for test and measurement methods and procedure standards. Ceased operations in 2011.

Electronic Wire and Cable
A length of conductive or semiconductive material used in an electronic application.

Electroplating
A method of electrically depositing metals of very precise compositions and thickness onto a base metal.

Electrostatic
Pertaining to static electricity or electricity at rest. A constant intensity electric charge

Electrostatic Coupling
The transfer of energy by means of a varying electrostatic field. Capacitive coupling.

Electrostatic Shield
A copper or laminated aluminum/mylar tape wrap around a signal or instrumentation circuit (pair, triad, etc.) to protect from the electric field radiated by a voltage source. The grounded shield intercepts static interference and carries it off to ground.

Elongation
The fractional increase in length of a material stressed in tension.

Elongation at Break
The tensile strain in a test piece stretched to breaking point, the conditions being such that the stress is substantially uniform over the cross - section.

Embossing
A marker identification by means of thermal indentation leaving raised lettering on the sheath material of cable.

Emergency management center (EMC)
A secondary traffic management center for emergency situations when the main traffic management center is unavailable or where additional monitoring or control is required.

Emergency Overload
Load which occurs when larger than normal currents are carried through a cable or wire over a certain period of time.

Emergency restoration kit (ERK)
A kit consisting of a length of optical cable, two closures, splice products, tools, and fixtures to assist in temporary or permanent restoration of cable repairs.

EMF
Electromotive force (voltage).

EMI
Electromagnetic Interference. Any electrical or electromagnetic interference that causes undesirable response, degradation, or failure in electronic equipment. Optical fibers neither emit nor receive EMI.

EMI Filter
A circuit or device containing series-inductive and parallel-capacitive components that provide a low impedance path for high-frequency noise around a protected circuit.

EMI Filtering
The reduction in strength of electromagnetic fields and noise that can interfere with and alter a valid transmitted signal traveling in/on a metallic wire. This is typically accomplished by shielding; it can also include use of ferrites or toroids and/or capacitive couplers.

Emulsion
A dispersion of fine particles in water. A heterogeneous system in which an immiscible liquid is distributed in fine drops in another liquid.

Enameled Wire
A conductor with a baked-on enamel film insulation. In addition to magnet wire, enameled insulation is used on thermocouple type wires and other wires.

Encapsulated Adhesive
An adhesive in which the particles or droplets of one of the relative components are enclosed in a protective film (microcapsules) to prevent cure until the film is destroyed by suitable means.

Encapsulation
Covering and sealing

Encircled flux (EF)
Defined by IEC 14763, TIA 455-203, and IEEE 802.3ae, EF is the most accurate test for determining optical attenuation for multimode fibers. Most often used in factory environments due to its complexity and equipment costs.

Encoder
A device that converts discrete component signals into a composite signal.

Encryption
The conversion of plain text into an unintelligible form from which the original meaning can be recovered.

End Bell
An accessory similar to a cable clamp that attaches to the back of a plug or receptacle. It serves as an adaptor for the rear of connectors.

End Cap Splice
An insulated splice in which two or more wires overlap and enter the splice from the same end of the barrel.

End finish
The quality of the end surface of a fiber prepared for splicing or terminated in a connector.

End group
Functional group at the end of a chain in polymers, e.g. carboxylic group.

End separation loss
The optical power loss caused by distance between the end of a fiber and a source, detector, or another fiber.

Endbell
An accessory similar to a cable clamp or strain relief which attaches to the back of a connector. It serves as an adapter for the rear of a connector.

Endface
The surface area of the fiber optic ferrule where the optical fiber is centered and polished.

Endless Rope
Rope whose two ends are spliced together

Ends
The number of wires or threads on a braider carrier.

Endurance Test
The procedure by which aircraft cable is tested for longevity in applications requiring cycles over a pulley or other device. This test differs from a pull test by simulating real world applications and environments

Energize
To apply rated voltage to a circuit or device in order to activate.

Energy Dissipation
Loss of energy from a system due to the conversion of work energy into an undesirable form, usually heat. Dissipation of electrical energy occurs when current flows through a resistance.

Engaging and Separating Force
The amount of force needed to engage and/or separate contact elements in mating connectors. See "Contact Pressure."

Enhanced Specialized Mobile Radio (ESMR)
The next generation of SMR, ESMR takes advantage of digital technology combined with cellular system architecture to provide greater capacity than existing SMR systems.

Enterprise PCS
A communication system that adds wireless capability to an in-building or campus communications network.

Enterprise System Connection (ESCON)
A proprietary IBM data communications system consisting of duplex fiber transmission of up to 1.2 Gb/s.

Entrance Facility
The entrance to a building for communications and power. It provides the transition between the outside plant and the premises. The entrance facility can connect to telecom, utility, or communication rooms or closets.

Entrance Facility, Telecommunications
An entrance to a building for both public and private network service cables (including antennae) including the entrance point at the building wall and continuing to the entrance room or space.

Entrance Point, Telecommunications
The point of emergence of telecommunications conductors through an exterior wall, a concrete floor slab, or from a rigid metal conduit or intermediate metal conduit.

Entrance Room or Space, Telecommunications
A space in which the joining of inter- or intra-building telecommunications backbone facilities takes place. An entrance room may also serve as an equipment room.

Environment
Aggregate of all conditions which externally influence a connector's performance.

Environmentally Sealed
A connector provided with gaskets, seals, potting, or other devices to keep out moisture, dirt, air, or dust which might lower its performance.

Epoxy
An adhesive used in the connector termination process.

Epoxy Resin
Plastic materials that become hard, infusible solids upon the addition of a hardening agent. Epoxy resins have excellent adhesive action, high chemical, solvent, and thermal resistance, and low shrinkage on curing.

Epoxyless Connector
A connector that requires no epoxy to hold the optical fiber to the connector.

Equal Level Far End Crosstalk (ELFEXT)
Is the same as FEXT, except that the coupled signal at the remote end is relative to the attenuated signal at the remote end on the pair the signal was applied to at the local end.

EQUAL LEVEL FAR-END CROSSTALK (ELFEXT)
A measure of the unwanted signal coupling from a transmitter at the near-end into a neighboring pair measured at the far-end relative to the received signal level measured on that same pair.

Equal Load Sharing
An even distribution of current between the parallel cables in a power circuit.

Equalizer
A device to vary frequency response to compensate for differences is a system.

Equalizing Thimbles
Special type of fitting used as a component part of some wire rope slings

Equilay
More than one layer of helically laid wires with the direction of lay reversed for successive layers, but with the length of lay the same for each layer.

Equilibrium modal distribution (EMD)
Steady-state modal distribution in multimode fiber, achieved some distance from the source, where the relative power in the modes becomes stable with increasing distance.

Equilibrium moisture content
The moisture content eventually attained in wood exposed to a given level of relative humidity and temperature.

Equipment Cable
A cable connecting equipment to a distributor.

Equipment Cable Cord
A cable or cable assembly used to connect telecommunications equipment to horizontal or backbone cabling.

Equipment Room
The room in which voice and data common equipment (for example, a Definity switch) is housed, protected, and maintained, and where circuit administration is done using the trunk and distribution cross connects.

Equipment Room, Telecommunications
A centralized space for telecommunications equipment that serves the occupants of the building. An equipment room is considered distinct from a telecommunications closet because of the nature of complexity or the equipment.

Equipment Subsystem
The part of a premises distribution system that includes the cable and distribution components in an equipment room and that interconnects system-common equipment, other associated equipment, and cross connects.

Erbium-doped fiber amplifier (EDFA)
An optical amplifier that uses active erbium-doped fiber and a pump source (laser) to boost or amplify the optical signal. Used in DWDM, CATV HFC, RF overlay and RFoG systems. Amplifies mostly in the C-band (1530 to 1565 nm).

Etch
A process, using either chemicals or plasma which roughens the surface of a wire to assist in bonding to or making the wire.

Etched Wire
A process applied to fluoro plastic wire in which the wire is passed through a sodium bath to create a rough surface to allow epoxy resin to bond the fluoro plastic.

EtherLEC
Ethernet Local Exchange Carrier

Ethernet
A data communications protocol for premises and local access networks (IEEE 802.3). Ethernet features variable length packets that allow data to be sent with less overhead.

Ethernet PON (EPON)
Based on IEEE 802.3ah protocol for Ethernet, EPON is a network data transport using a variable length packet structure up to 1,518 bytes at data rates up to 1,000 Mb/s over single-mode fiber. The EPON format uses up to 1:32 optical splitters and can use either one fiber bi-directionally (BX) or two fibers (LX) in low medium or high power configurations.

Ethylene Propylene Rubber (EPR)
An ozone resistant rubber consisting primarily of ethylene propylene copolymer (EPM) or ethylene propylene diene terpolymer (EDPM).

European Radio Message System (ERMES)
ERMES is the public Pan-European lank-based paging system.

European Telecommunications Standards Institute (ETSI)
One of the European organizations responsible for establishing common industry-wide standards for telecommunications.

Eutectic Solder
The most common solder alloy because of its low melting point (183oC/361oF). Can be any alloy that changes from a liquid to a solid state at a defined temperature.

Eutectic System
A eutectic system is a mixture of chemical compounds or elements that has a single chemical composition that solidifies at a lower temperature than any other composition made up of the same ingredients. This composition is known as the eutectic composition and the temperature at which it solidifies is known as the eutectic temperature. On a phase diagram the intersection of the eutectic temperature and the eutectic composition gives the eutectic point. Non-eutectic mixtures will display solidification of one component of the mixture before the other. Not all binary alloys have a eutectic point; for example, in the silver-gold system the melt temperature and freeze temperature both increase monotonically as the mix changes from pure silver to pure gold

Evaporation rate
The rate at which a material will vaporize compared with a known substance.

Excess loss
The amount of light lost in a coupler, beyond that inherent in the splitting to multiple output fibers.

Exit Angle
The angle between the output radiation vectors and the axis of the fiber or fiber bundle.

Exotherm
Exothermic materials give off heat when they cure. When large quantities cure all at one time, the amount of heat given off (the exotherm) can be high enough to melt plastic containers.

Exothermic
A chemical reaction which gives off heat.

Expanded Diameter
Diameter of shrink tubing as supplied. When heated the tubing will shrink to its extruded diameter.

Expanded ID
The specified minimum (as supplied) internal diameter of tubing.

Expanded Polyethylene
See Cellular Polyethylene

Extended Total Access Communications System (ETACS)
An analog cellular system used mainly in Europe. It has also been implemented in some areas in Japan, the United Kingdom, China, and other regions of the world. The ETACS was developed from the US Advanced Mobile Phone Service technology.

Extender
Substance added to an adhesive to reduce the amount of the primary binder required per unit area.

Extensibility
The ability of a sealant to stretch under tensile load.

External Interference
The effects of electrical waves or fields which cause spurious signals other than the desired intelligence, e.g. noise.

External Wiring
Electronic wiring which interconnects subsystems within the system.

Extra High Strength Strand
A grade of galvanized or bright strand

Extra Improved Plow
See "Grades, Rope"

Extraction Tool
A device used for removing removable contacts from a connector. A device used for removing taper pins from taper pin receptacles. (MIL-STD)

Extrinsic loss
Loss caused by imperfect alignment of fibers in a connector or splice such as lateral offset, angular misalignment, end separation, and end finish.

Extruded Cable
Cable with conductors which a re uniformly insulated and formed by applying a homogeneous insulation material in a continuous extrusion process.

Extrusion
A method of forcing thermoplastic, rubber or elastomer material under elevated temperature through a die to apply an insulation or a jacket to a cable.

Extrusion Failure
Failure that occurs when a sealant is forced too far out of a joint by compression forces. The sealant may be abraded by dirt or folded over by traffic.

Eye or Eye Splice
A loop with or without a thimble formed in the end of a wire rope

F-Block Carrier
A 10-MHz personal-communications-services carrier serving a basic trading area in the 1890-to-1895-MHz range paired with 1970-to-1975-MHz.

Fabry-Perot (FP) laser
A multilongitudinal mode laser diode with a semiconductor on each end to form a resonant chamber to create the lasing effect. Used in digital applications. Limited to 10 Gb/s speeds and used only for digital transmission.

Face Clearance
The distance between a glass plate and the edge of the stop.

Face Glazing
The method of glazing in which a rabbeted glazing recess, with no movable stop, is used and a triangular bead of compound is applied to the face of the lite and extended onto the recess (ASM C 717-07a).

Face Seal
A sealing of mated connectors over the whole area of the interface to provide sealing around each contact. (MIL-STD) Also called Interfacial Seal

Factor of Safety
Ratio of breaking strength of a wire rope to total rope stress

Failure, Adhesive
Rupture of an adhesive bond such that the separation appears to be at the adhesive substrate interface.

Failure, Cohesive
Condition of bond failure in which the adhesive falls apart.

Failure, Substrate
Condition of bond failure in which the substrate falls apart. The cohesive strength of the adhesive and the adhesive forces between the adhesive and substrate exceed the internal strength of the material being bonded.

Fall-off
Condition in which a tape pulls completely away from the surface to which it is applied and drops off.

False Ceiling
A ceiling that creates an area or space between the ceiling material and the structure above the material. Synonym: Drop Ceiling, Suspended Ceiling.

Fanout
A device similar to a concentrator in that it provides multiple access to a single backbone tap.

Fanout kit
A kit designed for loose tube cable structures with multiple fibers per buffer tube. The fanout kit provides a 900-?m tubing over each 250-?m coated fiber strand, which allows for additional protection.

Far End Crosstalk (FEXT)
Refers to the undesired coupling of signals from the transmit pair onto the receive pair at the other (=far) end. FEXT isolation is also expressed in dB. For some applications this is an important parameter, for most applications however, the NEXT values are more important.

Far-End Crosstalk Loss (FEXT)
A measure of the unwanted signal coupling from a transmitter at the near-end into a neighboring pair measured at the far-end.

Farad (F)
The standard unit of capacitance whereby a charge of one coulomb produces a one volt potential difference. It indicates the charge per potential difference.

Faraday Shield
A conductive material used to contain or control an electric field. Placed between the primary and secondary windings of a transformer, it reduces coupling capacitance and common-mode noise. The shield provides electrostatic shielding while passing electromagnetic waves and requires no ground.

Fard
A unit of electric capacity.

Fast Ethernet
IEEE 802.3 standard operating at 100 Mb/s.

Fat Fiber
FOC specialty fiber market with connectors for more fiber sizes than any other company in the world (more than 40 hole sizes of SMA connectors, over 10 sizes of FCs, custom hole sizes (i.e., other than 125 um) in ST, SC, LC and other connectors).

Fatigue
Term commonly applied to progressive fracture of wires of a rope

Fatigue failure
Failure of a material as a result of rapid cyclic deformation

Fatigue Resistance
Resistance to metal crystallization which leads to conductors of wires breaking from flexing.

Fault
Break or stress in the continuity of the optical fiber’s normal performance.

Fault Find
A diagnostics feature on the IDEAL LAN Testers that allows you to determine where in a link a fault is located. (also see DOWNLINE IMPEDANCE)

Fault Finder
A simplified OTDR used to locate breaks in spans of fiber. See fiber break locator.

Fault Ground
A fault to ground.

Faying Surface
The surface of an adherend which makes contact with another adherend.

FC CONNECTOR
A connector type used primarily for Singlemode fiberoptic cable. It offers precise alignment of the cable with respect to the transmitter and detector. Using a threaded receptacle and a locator notch, once installed the position is maintained with absolute accuracy.

FDDI (Fiber Distributed Data Interface)
A standard for a 100 Mbs fiber optic area network.

Feathering
The tapering of an adherend on one side to form a wedge section, as used in a scarf joint; in pressure sensitive tapes, a jagged, irregular paint line frequently characterized by small "feathers" of the top-coat projecting into the masked area.

Federal Communications Commission (FCC)
A board of five commissioners, appointed by the President, that regulates all electronic communications systems originating in the United States, including telephone systems. This government agency is responsible for the allocation of radio spectrum for communication services in the US

Feed-Through Insulators
Insulators that carry a metal conductor through the chassis while preventing the 'hot' lead from shorting to the ground chassis.

Feed-Thru
A connector or terminal block usually having double-ended terminals which permit simple distribution and bussing of electrical circuits. Also used to describe a bushing in a wall or bulkhead separating compartments at different pressure levels with terminations on both sides.

Feedback
Energy that is extracted from a high-level point in a circuit and applied to a lower level. Positive feedback reduces the stability of a device and is used to increase the sensitivity or produce oscillation in a system. Negative feedback, also called inv

Feeder Cable
In telecommunication or CATV systems, the transmission cable from the head end (signal pickup) to the trunk amplifier. Also called a Trunk Cable.

Feedthrough
(1) A conductor that connects patterns on opposite sides of a PCB. Also called Interfacial Connection; (2) A connector or terminal block, usually having double-ended terminals which permit simple distribution and bussing of electrical circuits.

FEP (Fluorinated Ethylene-Propylene)
Copolymer of PTFE and hexafluoropropylene. Electrical properties similar to PTFE, but temperature limited to 400°F (204°C).

Ferrite
Ferrimagnetic ceramic non-conductive compound material used to prevent high frequency electrical noise from entering or exiting the equipment.

Ferrite Material
Material made by calcining a combination of metal oxides sintered into tiles. Material only a few millimeters which absorbs low frequencies. These tiles may be used with dielectric materials or as a hybrid combination with dielectric pyramids.

Ferrous
Composed of and/or containing iron. A ferrous metal exhibits magnetic characteristics.

Ferrule
A component of a connector that holds fiber in place and aids in its alignment, usually cylindrical in shape with a hole through the center. A short tube used to make solderless connections to shielded or coaxial cable. An item molded into the plastic inserts of multiple contact and fiber optic  retaining springs can bear. Connections to provide strong, wear-resistant shoulders on which contact. A substance that is added to a material to improve its solidity, bulk , or other properties.

Fiber
Any filament or fiber, made of dielectric materials, that guides light. Also, single discrete element used to transmit optical (light wave) information. See also Fiber Optics.

Fiber Amplifier
Most common are the erbium doped fiber amplifiers (EDFAs), semiconductor optical amplifiers (SOAs), and Raman amplifiers, which are used to increase signal gain without electrical conversion.

Fiber Bragg grating (FBG)
A piece of photo-refractive fiber that is exposed to high intensity UV interference patterns, causing it to reflect a specific wavelength while being transparent to all other wavelengths. Used as a filter in WDM systems.

Fiber Break Locator
A low-cost OTDR that is used to locate breaks in optical fiber cables.

Fiber Centers
Cords or rope made of vegetable fiber or synthetic fiber used in the center of a strand

Fiber Channel
A high speed point-to-point, ANSI Optical Communications Standard that supports data transfer rates up to 1,062.5 Mbs (1 Gps).

Fiber Cleaving
Controlled fracture of an optical fiber along a crystalline plane which results in a smooth surface.

Fiber Coating
A UV-cured material immediately surrounding the glass cladding that serves to protect the integrity of the fiber from surface damage and stresses. Normally 250 ?m for outside plant cables and 900 ?m for indoor cables.

Fiber Connector (FC)
A keyed connector with threaded coupling mechanism that has 2.5-mm ferrule. Mostly used in single-mode systems and test equipment.

Fiber Demarcation Box (FDB)
A fiber demarcation box provides a service provider with a customer disconnection point, either via a splice or connector interface. Slack cable storage and battery backup are stored here as well.

Fiber Dispersion
Pulse spreading in a fiber caused by differing transit times of various modes.

Fiber Distributed Data Interface (FDDI)
100 Mb/s ring architecture data network.. An American National Standards Institute (ANSI) standard for a fiber-based token ring physical and data link protocol that operates at a 100-Mbps data transfer rate. A duplex, counter-rotating, self-healing ring communication standard (ANSI X3T9) that provides a 100 Mb/s data format. Often used to interconnect low-speed protocols such as Token Ring and Ethernet.

Fiber distribution unit (FDU)
Enclosures that house and organize groups of fibers.

Fiber Identifier
A device that clamps onto a fiber and couples light from the fiber by bending, to identify the fiber and detect high speed traffic of an operating link or a 2 kHz tone injected by a test source.

Fiber in the loop (FITL)
An outside plant architecture deployed by telephone companies to provide broadband services to subscribers. In this architecture, SONET/SDH fiber runs from the telephone company central office to an optical networking unit. From the ONT, subscribers are served in a star topology with a drop of coax, twisted pair, or composite coax/twisted pair.

Fiber Optic Building Cable (LGBC)
A fiber optic cable in which individual optical fibers are formed into a cable for primary use in side building.

Fiber Optic Bundle
A number of fibers grouped together (rigid or flexible), usually carrying a common signal (or an image, or a conduit for transfer of light power).

Fiber Optic Cable
A communications cable that consists of one or more optical fibers, each capable of transmitting data via modulated light waves. Loose buffered types for outside plant applications can be armored or dielectric stranded or central tube designs. Applications include aerial figure-8, ducted, direct buried, all dielectric self-supporting (ADSS), and optical power ground wire (OPGW). Indoor designs are tight buffered breakout or distribution types with cable jackets designed to meet building codes for use in plenum, riser, and low smoke zero halogen environments.

Fiber Optic Center Catalog
http://focenter.com/product-categories/

Fiber Optic Connectors
Connectors designed to connect and disconnect either single or multiple optical fibers repeatedly. Fiber optic connectors are use to connect fiber cable to equipment and interconnect cables.

Fiber Optic Cross Connection
Fiber optic apparatus for terminating cable in couplings. Designed for high-density cross-connection fields, the apparatus can terminate up to 72 fibers on each shelf, with up to nine shelves in a bay frame. Single shelves can also be wall mounted. Cross connections are handled with fiber optic patch cords. See also Patch Cord.

Fiber Optic Cross-Connect (LGX) Distribution System
A component of fiber optic cross-connect hardware. This component accommodates 24-216 fiber terminations. Also referred to as an LGX or shelf or frame.

Fiber Optic Interconnect
An interconnection unit used for circuit administration and built from modular cabinets. It provides interconnection for individual optical fibers but, unlike the fiber optic cross-connect panel, it does not use patch cords or jumpers. The fiber optic interconnect provides some capability for routing and rerouting circuits, but is usually used where circuit rearrangements are infrequent.

Fiber Optic Splice
A fiber optic cable splice is used to join together 2 or 24 fiber optic cable ends, permanently.

Fiber Optic Test Procedure (FOTP)
Standardized methods for testing various fiber optic components, as specified in the TIA-455 standard.

Fiber Optic Test Protocols
A series of test procedures defined by the FO 6.2 committee of TIA. The procedures cover a wide number of situations, for example, verification by manufacturers of cable specifications, cable bend radius, connector manufacturing, fire rating, and field testing of fiber optic installations.

Fiber Optics
A lightwave or optical communications system in which electrical information is converted to light energy transmitted to another location through optical fibers, and is there converted back into electrical information. Branch of optical technology dealing with the transmission of radiant power through fibers made of transparent materials such as glass, fused silica, or plastic. Term used to describe links used for voice, video, data, medical, sensing, and illumination applications. All use optical fibers to transmit or receive optical signals or power. Light transmission through flexible transmissive fibers for communications or lighting.

Fiber Optics LAN Section
Known as FOLS, a group operating within the trade association operation of TIA. FOLS is dedicated to promoting the common interests of TIA members involved in fiberoptic telecommunications.

Fiber Proof Testing
A mechanical tensile test used to measure the axial strength of an optical fiber, normally 100 kpsi.

Fiber Saturation Point
The moisture content of wood at which all unbound moisture has been eliminated. This is typically about 30% Moisture Content.

Fiber Sensor
A sensing device in which the active sensing element is an optical element attached directly to an optical fiber. The measured quantity changes the optical properties of the fiber so that it can be detected and measured.

Fiber surface finish
The quality of the polishing at the end of the fiber (1 mm, 0.3 mm, etc.). Some terms that describe a poor surface finish are: mist, hackle, chipped, or cracked.

Fiber Tear
In an FRP adhesively bonded joint, failure occurring exclusively within the fiber reinforced plastic matrix, charisterized by the appearance of reinforcing fibers on both ruptured surfaces.

Fiber to the antenna (FTTA)
See Fiber to the cell.

Fiber to the building/business (FTTB)
A topological reference to a network that supports multiple subscribers in a single structure, i.e., a business or a building. Multiple dwelling unit (MDU) defines residential use and multiple tenant unit (MTU) defines business units.

Fiber to the cell (FTTCell)
Fiber to the cell tower. Used to provide greater bandwidth and to transition to IP requirements using Ethernet.

Fiber to the curb/customer (FTTC)
Distribution of communication services by providing fiber optic links to a central point in each neighborhood and continuing to the homes by either twisted pair or coax.

Fiber to the desk (FTTD)
Transmission system using fiber optics from transmitter todesktop.

Fiber to the home (FTTH)
Distribution of communication services by providing fiber optic links all the way to each house. Protocols include active Ethernet and PON systems as defined by the IEEE, ITU, and SCTE.

Fiber to the node (FTTN)
An access network in which fiber is used for part, but not all, of the link from the OLT to the end user. An optical-to-electrical conversion takes place at a node, which typically serves a neighborhood. The terminal network segment is usually twisted copper pair (FTTC) or coaxial cable (HFC). Most current CATV and telephony networks have FTTN architectures.

Fiber tracer
An instrument that couples visible light into the fiber to allow visual checking of continuity and tracing for correct connections.

Fiber Tubing
A loose, crush-resistant cylinder applied over individual fibers to provide mechanical protection.

Fiber-reinforced plastic (FRP)
A plastic that contains fibers in various forms such as cloth, mat, strands, or chopped to enhance properties.

Fiberglass
The trademark for glass which is formed into thin fibers and twisted and plied into yarns. It is used as protective braiding for cables. Normally saturated with silicone-base varnish to seal against moisture.

FiberSmart
Fiber Optic Center term on their strong technical area in the manufacturing and testing of fiber optic cable assemblies, also known as patch cords. FOC is the only company in the world that can supply every piece of equipment needed to strip the cable, dispense and cure the epoxy, polish the terminated connector and perform all three kinds of testing: optical, geometry and visual inspection.

Fibre Channel
A high-speed interconnection ANSI standard for connecting supercomputers with peripheral devices up to 10 km away at transmission rates over 1 Gb/s. Used for the broadcast industry, storage area networks, and data centers.

Field
An area of influence around a magnet or electric charge.

Field Coil
A suitable insulated winding to be mounted on a field pole to magnetize.

Field Effect Transistor (FET)
One of the two main amplifier types. FETs have limited frequency but are less noisy than bipolar circuits.

Figure 8 cable
A type of cable with a built-in messenger designed for aerial installations.

Figure 8 polishing
When a connector is polished on a lapping film/plate combination in a Figure 8 pattern to minimize scratches by using a different area of the lapping film.

Filament
Fiber characterized by extreme length.

File Server
A device found on local area networks which sends requested files and programs to requesting nodes and stores files sent from nodes.

Fill, Gap
Ability of an adhesive to fill the space between substrates and hold the substrates in place.

Filled Cable
A telephone cable construction in which the cable core is filled with a material that will prevent moisture from entering or passing through the cable.

Filler
(1) A material used in the cable to fill large interstices between electrical components; (2) A substance, often inert, added to a compound to improve properties and/or decrease cost.

Filler Sheet
Sheet of deformable or resilient material which, when placed between the assembly to be bonded and the pressure applicator, or when distributed within a stack of assemblies, aids in providing uniform application of pressure over the area to be bonded.

Filler Wire
Small auxiliary wires in a strand for spacing and positioning other wires

Fillers
Non-conducting components cabled with the uninsulated conductors or optical fibers to impart roundness, flexibility, tensile strength, or a combination of all three, to the cable.

Fillet
That portion of an adhesive which fills the corner or angle formed where two adherends are joined.

Film
A thin plastic sheet. Uniform, homogenous on-fibrous synthetic webs.

Film Adhesive
An adhesive in film form, with or without a carrier, usually set by means of heat and/or pressure. The main advantage is uniformity of glueline thickness.

Filter
A devise which blocks the flow of EMI current while passing the desired 50/60/400-Hz current. When used in communications circuits, it suppresses unwanted frequencies and noise, or separates channels.

Filter Contact
A contact which provides R.F.I. suppression without altering its normal function.

Final Polish Film

Fine Stranded Wire
Stranded wire with component strands of 36 AWG or smaller.

Finger Joint
See finger joint under joint.

Finger Stock
A beryllium copper electrical gasket used to bond metal panel members on doors, sills or covers.

Firestop
A material, device, or assembly of parts installed in a cable system in a fire-rated wall or floor to prevent passage of flame, smoke, or gasses through the rated barrier.

Firmware
Operating instructions for a processor permanently stored in devices such as EPROM’s, and ROM’s which are hardware.

First Article
A sample part or assembly manufactured prior to the start of production for the purpose of assuring that the manufacturer is capable of manufacturing a product which will meet the requirements.

Fitting
Small auxiliary wires in a strand for spacing and positioning other wires

Five Nines
Any system operating 99.999% of the time.

Fixed Contact
A contact which is permanently included in the insert material.

Fixture Time
Time needed for adhesive to reach sufficient strength to allow pieces to be handled and moved.

Fixture Wire
Fixture wires according to the National Electrical Code are designed for installation in lighting fixtures and in similar equipment where enclosed or protected and not subject to bending or twisting in use. They also are used for connecting lighting fixtu

Fixturing
The wires and connectors that connect the device-under-test to the tester.

Flame Resistance
Ability of the material to extinguish flame once the source of heat is removed.

Flame Retardance
Ability of a material to p revent the spread of combustion by a low rate of travel so the flame will not be conveyed.

Flammability
The measure of the material's ability to support combustion.

Flammability Rating
Test methodologies of various organizations designed to simulate exposure to flame and burning, and the results of a material when tested under a specific methodology. Frequently used tests are UL94 (for testing materials as slabs or plaques), UL VW-1 or CSA FT1 (testing cable in a verticaly orientation), NEC CL2 (testing cables for general purpose communications which are installed within buildings), CSA FT6 (testing cable for horizontal flame and smoke)

Flammability Test
A test to determine the ability of a cable to resist ignition when placed near a source of heat or flame and to self-extinguish when removed from this source.

Flammable
Describes any material that will ignite easily and burn rapidly.

Flange Connector
A projection extending from or around the periphery of a connector with provisions to permit mounting the connector to a panel or to another mating connector half.

Flash
A thin film of material formed at the sides of a forging, casting or molded part where some of the material is forced between the faces of the dies or mold halves

Flash Memory
Flash Erasable Programmable Read-only Memory is a form of computer semiconductor storage. It allows data in electronic format to be held without loss (unlike RAM) for an indefinite period (like ROM), and for the contents to be changed. It is a popular type of removable storage used for transporting data between recording devices and a PC.

Flash Plating
The application of extremely thin deposits of a plating material for environmental protection or as a base for a subsequent layer of plating.

Flash point
The lowest temperature at which the vapors being given off by a substance can be ignited.

Flashover
A disruptive discharge around or over the surface of a solid or liquid insulator.

Flat Braid
A woven braid of tinned copper strands rolled flat at time of manufacture to a specified width.

Flat Cable
A cable in flat form, where the conductors lying parallel longitudinally but essentially with flat surfaces.

Flat Conductor
A wire having a rectangular cross section as opposed to round or square conductors.

Flat Conductor Cable
A cable with a plurality of flat conductors.

Flat Polish
A highly-reflection ferrule endface condition where fiber optic and ferrule tip are polished flat. Normally used with multimode fibers.

Flat Rope
Wire rope made of parallel alternating right lay and left lay ropes sewn together by relatively soft wires

Flat Under Carpet Cable
A cable containing one or more cores, each formed of a group of wires, the diameters of the wires being sufficiently small to afford flexibility.

Fleet Angle
Angle between position of a rope at the extreme end wrap on a drum, and a line drawn perpendicular to the axis of the drum through the center of the nearest fixed sheave

Flex Damage
Damage, usually occurring where a cord enters the housing, which is caused by the sharp bending of the cord. A strain relief or cable clamp restricts the concentration of flexing.

Flex Life
The number of cycles that a cable can withstand before failure when bent around a specific radius. The ability of a cable to bend many times before breaking.

Flex Life Test Types
Testing methodologies used to evaluate the durability and reliability of a cable or assemly under repeated bending. Three methods are frequently used: Weighted Bend, Bend, or Rolling Bend. The Weighted Bend test holds a section of the cable aligned within a fixed holder and with a weight attached to the calbe below the holder (applied load). At a specific distance from the holder, the free end is bent to a 90 degree angle in one direction and then reversed to a 90 degree angle in the opposite direction. This is one flex cycle. The Bend test is the same as the Weighted Bend test without a weight (no load) attached to the cable. The Rolling Bend test holds one end of the cable in a fixed holder, the cable is formed into a U shape, and the free end of the cable is moved back and forth keeping the sides of the U at a fixed distance apart during the cycling

Flexibility
The ability of a cable to bend in a short radius (also see Limpness).

Flexible
The quality of a cable or cable component which allows for bending under the influence of outside force, as opposed to limpness which is bending due to the cable's own weight.

Flexible Cable
A cable containing one or more cores, each formed of a group of wires, the diameters of the wires being sufficiently small to afford flexibility.

Floating
Referring to a circuit which has no connection to ground.

Flood Wiring
The concept of wiring for future growth, by providing full coverage of information outlets.

Floor Distributor
The distributor used to connect between the horizontal cable and other cabling subsystems or equipment (see telecommunications closet).

Flory-Huggins theory
A thermodynamic theory of polymer solutions, first formulated independently by Flory and by Huggins, in which the thermodynamic quantities of the solution are derived from a simple concept of combinational entropy of mixing and a reduced Gibbs-energy parameter, the `X parameter'. The X parameter is a numerical parameter employed in the Flory-Huggins theory, which accounts in the main for the contribution of the non-combinational entropy of mixing and for the enthalpy of mixing. (IUPAC)

Flow
Movement of an adhesive during the bonding process before the adhesive is set.

Fluorinated Ethylene Propylene (FEP)
FEP is similar to polytetrafluoroethylene (PTPE) but has a melting point of about 50° C lower and slightly different physical properties.

Fluorocarbon Films
A film with very high and low temperature limits, and excellent electrical characteristics. Typically exhibit a very slippery on-sticking surface. Note: One example is DuPont’s Teflon®.

Fluoropolymer
A polymer that contains atoms of fluorine. Typical fluoropolymers are TFE, FEP, PFA, ECTFE and PVF.

Flux
(1) The lines of force which make up an electrostatic field; (2) The rate of flow of energy across or through a surface; (3) A substance used to promote or facilitate fusion .

Foam Polyethylene
See Cellular Polyethylene.

Foam Skin Cable
A cable utilizing a foamed polyolefin inner layer covered by a solid polyolefin skin as the conductor insulation.

Foamed Adhesive
An adhesive whose apparent density has been decreased by the presence of numerous gas-filled cells throughout its mass.

Foamed Plastics
Resins in flexible or rigid sponge formed with the cells closed or interconnected. Foamed insulations provide low dielectric contestants and weight savings.

Foamskin
Polyethylene foam insulation with polyethylene outerskin.

FOC Corporate Citizen
Fiber Optic Center support of select non-profit organizations by annual donations and hours of volunteerism.

FOC TV
Fiber Optic Center's video library of training, content and product demonstrations

Foil screened twisted pair cable (FTP)
A cable that use's a metallic Foil to surround the conductors in a Twisted Pair cable.

Foils
A thin supporting film of continuous sheet such as plastic foil, metal foil, laminated foil etc. for static shielding, contacts and other electrical applications.

Follower
A sleeve used to compress a grommet which tightens the seal around the wire entering the connector.

Footprint
1) The area of the earth’s surface covered by a satellite signal.  2) The area of a printed circuit board covered by an electronic component such as a connector, IC, etc.

Forward error correction (FEC)
A method to improve the performance of large-capacity optical transmission systems. System designs employing FEC can accept relatively large BER (better than 10–12) in the optical transmission line before encoding.

Four wave mixing (FWM)
A collective name for a group of nonlinear processes where up to three different incident waves interact in the medium, resulting in a fourth wave.

Four-Wire Circuit
A transmission circuit using a transmit pair and a receive pair, or four wires altogether.

Frame
A metallic structure for hanging switch hardware.

Frame Relay
A packet-based technology that provides LAN-to-WAN connectivity over telephone lines at up to 1.5 Mb/s.

FRD (Fire Retardant)
A rating used for cable with Teflon or equivalent jacket and insulation. Use this cable when local fire codes call for low flame and low smoke, or when cable is run through a forced-air plenum.

Free Connector
A connector for attachment to the free end of a wire or cable.

Free Radical
A chemical component that contains a free electron which covalently bonds with a free electron on another molecule.

Freely-Draining
An adjective referring to a chain macromolecule the segments of which produce such small frictional effects when moving in a medium such that the hydrodynamic field in the vicinity of a given segment is not affected by the presence of other segments. Thus, the solvent can flow virtually undisturbed through the domain occupied by a freely-draining macromolecule. degree of polymerization the number of monomeric units in a macromolecule or oligomer molecule. (IUPAC)

Freeze/thaw stability
The ability of a product to remain usable after it has been frozen and thawed.

Frequency
The number of cycles, now expressed as hertz, by an alternating current in one second. The hertz is equivalent to the older unit cycles per second.

Frequency Division Multiplexing (FDM)
Two or more signals combined at different frequencies so they can be transmitted as one signal.

Frequency Modulation (FM)
A scheme for modulating a carrier frequency in which the amplitude remains constant but the carrier frequency is displaced in frequency proportionally to the amplitude of the modulating signal. An FM broadcast is practically immune to atmospheric and man-made interference.

Frequency Re-Use
Because of their low power, radio frequencies assigned to one channel in a cellular system are limited to a single cell. Carriers are free, however, to re-use the frequencies again in other cells in the system without causing interference

Frequency Response
The characteristic of a device denoting the range of frequencies over which it may be used effectively.

Frequency-Division Muliplexing (FDM)
Simultaneous transmission of two or more messages over the same cable medium. Also called Multiplexing.

Fresnel reflection
Reflection of a portion of the incident light at a planar interface between connectors, mechanical splices, or two homogeneous media having different refractive indices.

Fretting
A condition whereby mated surfaces move slightly and continually expose fresh metal. The exposed metal oxidizes and builds up until electrical continuity of the system is broken.

Fretting Corrosion
A form of excellerated oxidation that appears at the interface of contacting materials undergoing slight cyclic relative motion. All non-noble metals (i.e. tin) are susceptible to some degree of fretting corrosion and will suffer contact resistance increases.

Frictional Coefficient
A tensor correlating the frictional force F, opposing the motion of a particle in a viscous fluid, and the velocity u of this particle to the fluid. (IUPAC)

Front Mounted
A connector mounted on the outside of a panel or box with its mounting flange outside the equipment. (MIL-STD) A front mounted connector can only be installed or removed from the outside of the equipment.

Front Release Contacts
Connector contacts are released form the front side of the connector and then removed from the rear (wire side) of the connector. The removal tool engages the front portion of the contact and pushes it out the rear where it is removed by hand.

Full Cycling Control
Controls placed on the crimping cycle of crimping tools forcing the tool to be closed to its fullest extent completing the crimping cycle before the tool can be opened. (MIL-STD)

Full Duplex
In contrast to half-duplex devices, full duplex ones allow permanent, simultaneous two-way transmission of information, without interaction or interference of receive and transmit signals.

Full Duplex Ethernet
Full Duplex Ethernet will allow nodes to transmit and receive data at the same time, bringing aggregate throughput to 20 Mb/s. The CSMA/CD protocol may have to be disabled for the full duplex mechanism to function.

Full Duplex Transmission
1) Data transmission over a circuit capable of transmitting in both directions at the same time.  2) Synonymous with full duplex transmission. Also called Duplex Transmission.

Full spectrum wavelength division multiplexing (FSWDM)
A technology platform that uses spectrally enriched optical pulses for signal transmission at speeds of 10 Gb/s and higher.

Full width half maximum (FWHM)
Used to measure the spectral width of light sources. Measure the spectral width at 3 dB (half power from peak) and at the full width of the source’s power peak.

Full/full duplex
The primary can transmit to one secondary while simultaneously receiving from another secondary. In a typical multidrop LAN, the primary operates in full/full duplex mode while the secondaries operate in a half duplex mode.

Functional Group
A group of atoms on a monomer that can react with a group of atoms on a second monomer (Example: -COOH)

Funnel Entry
Flared or widened entrance to a terminal or connector wire barrel.

Fuse
A safety device consisting of a strip of wire that melts and breaks an electric circuit if the current exceeds a safe level.

Fuse Wire
Wire made from an alloy that melts at a relatively low temperature .

Fused Coating
A metallic coating which has been melted and solidified, forming a metallurgical bond to the base material.

Fused Conductors
Individual strands of heavy tinned copper wire stranded together and then bonded together by induction heating.

Fused Spiral Tape
A PTFE insulated hookup wire. The spiral wrapped conductor is passed through a sintering oven whereoverlaps are fused together.

Fusion splicer
An instrument that splices fiber by fusing or welding the fibers, typically by an electric arc. A mechanical device that optically joins optical fibers by discharging voltage between two electrodes. Variations include the single fiber and ribbon fixed V-groove types, the profile alignment splicer (PAS) and the local injection detection (LID), both of which are categorized as core alignment splicers.

G -PON encapsulation method (GEM)
A method of data encapsulation over the G-PON network, similar to ATM, that uses variable length frames to transport up to an encapsulated payload of 1500 bytes. Capable of sending ATM cells or Ethernet packets over the network.

G round Potential
Zero potential with respect to the ground or earth.

Gage
The physical size of a wire, as in American Wire Gage (AEG). Can also be used in reference to determining connector interface critical dimensions.

Gain
The increase of voltage, current or power over a standard or previous reading. Usually expressed in decibels. Increased backscatter inherent within OTDR. Fiber measurements due to different core sizes or core mismatch. A gainer refers to an OTDR signature that shows splice loss in one direction and “gain” of the reflected signal in the opposite direction.

Gain flattening filter (GFF)
Due to nonlinearities in the amplitude, GFFs are used to restore wavelengths to their approximate intensities after they have been amplified by erbium-doped fiber amplifiers. Also known as a gain equalization filter or dynamic gain equalizer.

Galvanize
To coat with zinc to protect against corrosion

Galvanized Rope
Rope made of galvanized wire

Galvanized Steel Wire
Steel wire coated with zinc.

Galvanized Strand
Strand made of galvanized wire

Galvanized Wire
Wire coated with zinc

Galvanometer
An instrument for detecting or measuring small electrical current.

Gang Disconnect
A connector that permits the rapid and simultaneous connection and disconnection of two or more electrical circuits. (MIL-STD)

Gang Strip
Simultaneous stripping of all conductors in a flat or ribbon cable.

Gap Fill
Ability of an adhesive to fill the space between substrates and hold the substrates in place.

Gap-Filling Adhesive
An adhesive capable of forming and maintaining a bond between surfaces that are not close-fitting. Discussion—Close-fitting is relative to a given material and industry; for example, standards in construction differ from standards in electronics. Some adhesives will bond by bridging without completely filling the gap, others by filling the gap completely.

Gas Filled Cable
A self-contained pressure cable in which the pressure medium is an inert gas having access to the insulation.

Gas Tightness
The characteristic of a contact which is impervious to ingress by corrosive gasses.

Gas-tight
The characteristic of a contact that is impervious to ingress by corrosive gases. The common area between mated-metal surfaces from which gas vapours and impuities are excluded.

Gasket
A component made from an elastomer, such as rubber, to provide an environmental seal in the interface of a connector pair. Also called a "grommet".

Gateway
1) A node common to two or more networks through which data flows from network to network. The gateway may reformat the data as necessary and also may participate in error and flow control protocols. Used to connect LANs employing different protocols and to connect LANs to public data networks. See also Port.  2) A function designed to facilitate electronic access by users to remote services. Gateways provide a single source where users can locate and gain access to a wide variety of services.

Gauge
A term used to denote the physical size of a wire.

Gel
A semisolid system consisting of a network of solid aggregates in which liquid is held.

Gel-permeation chromatography
A separation technique in which separation mainly according to the hydrodynamic volume of the molecules or particles takes place in porous non-adsorbing material with pores of approximately the same size as the effective dimensions in solution of the molecules to be separated. (IUPAC)

Gelation
Formation of a gel.

Generic Cabling
A structured telecommunications cabling system, capable of supporting a wide range of applications. Generic cabling can be installed without prior knowledge of the required applications. Application-specific hardware is not a part of generic cabling.

Genlock
One process of timing and phasing a local television signal to a remote signal.

Geophysical Cable
Cable used in exploring for underground oil deposits.

Geostationary Satellite
A satellite whose speed is synchronized with the speed of the earth’s rotation so that it is always in the same spot over the earth (geo-synchronous orbit). Most geo-synchronous satellites operate 22,300 miles above the equator.

Ghost
An OTDR signature caused by an optical echo that occurs when light reflects off two reflective surfaces, creating a false image at double the distance from the initial event.

GHz
See Gigahertz.

Giga (G)
A prefix meaning one billion.

Gigabit
One billion bits of information.

Gigabit Ethernet
IEEE 802.3z. A standard for a high-speed Ethernet, capable of transmitting data at one billion bits per second. It provides increased network bandwidth and interoperability, and can be used in backbone environments to interconnect multiple lower-speed Ethernet systems.

Gigabit PON (G-PON)
Standardized in ITU-T G.984, G-PON handles data rates up to 2.5 Gb/s and allows split ratios up to 1:64. The standard features the G-PON encapsulation method (GEM), which allows for the transmission of Ethernet packets and ATM cells.

Gigahertz (GHz)
A unit of frequency equal to one billion hertz.

Gimmick
A short length of wire soldered onto a circuit component and used as a small adjustable capacitor.

Glass Blank
The pure, solid glass mass formed after sintering an oxide preform. This glass blank undergoes a drawing process to become optical fiber.

Glass Transition Temperature (Tg)
The temperature at which an adhesive will become markedly less elastic and flexible.

Global Positioning System (GPS)
A network of satellites developed by the US Department of Defense that provides precise location determination to special receivers.

Global System for Mobile Communications (GSM)
The European digital cellular transmission standard which has been adopted by several other countries around the world for cellular and personal communications services. It was originally called the Groupe SpecialeMobile.

Glue
Originally, a hard gelatin obtained from hides, tendons, cartilage, bones, etc. of animals. Also, an adhesive prepared from this substance by heating with water. Through general use the term is now synonymous with the term “adhesive.”

Glue (archaic)
A hard gelatin obtained from hides, tendons, cartilage, bones, etc., of animals, and also an adhesive prepared from this substance by heating with water.

Glue line
The layer of adhesive that attaches two substrates. Same as bond line.

Glue reel
A series cold clamps arranged and used like a Ferris wheel. This permits a large number of panels to be clamped and stored within a small area.

Gold
The standard coating for contacts over a base of either nickel or copper. Used primarily as a coating or plating material because of its electrical properties.

GOS
Grade of Service

Gosip
Government OIS Procurement

Gov
“Government;” one of the top-level Internet domain names

GPIB
General purpose interface bus. Also known as the IEEE-488 bus. One method of providing communication between various test equipment and controllers .

Graded index (GI)
A type of multimode fiber which used a graded profile of refractive index in the core material to correct for dispersion.

Graded Index Fiber (Fiber Optic)
A multimode fiber whose core refractive index increases in controlled fashion outward from the axis and matches the cladding refractive index at the core-clad interface. Has greater bandwidth than step index fiber, but less bandwidth than single mode fiber.

Graded-Index
A type of optical fiber in which the refractive index of the core is in the form of a parabolic curve, decreasing toward the cladding. This type of fiber provides high bandwidth capabilities.

Graded-Index Fiber
An optical fiber core that has a non-uniform index of refraction. The core is composed on concentric rings of glass, which have refractive indices that decrease from the center axis. The refractive index is changed in a systematic way from the center to t

Graded-index multimode fiber (GI-MMF)
A type of multimode fiber where the refractive index of the fiber core decreases radically towards the outside of the fiber. Four types of GI-MMF have been specified in IEC 60793-2: legacy OM1 (62.5/125) and OM2 (50/125) fibers and the newer, high bandwidth, laser-optimized OM3 and OM4 fiber (both 50/125), designed for VCSEL lasers and Gigabit data rates.

Graded-index plastic optical fiber (GI-POF)
A plastic multimode fiber with a bandwidth of up to 3 GHz per 100 meters.

Grades, Rope
Classification of wire rope by its breaking strength. In order of increasing breaking strengths they are Iron, Traction, Mild Plow Steel. Plow Steel, Improved Plow Steel, Extra Improved Plow Steel

Grades, Strand
Classification of strand by its breaking strength. In order of increasing breaking strengths they are Common, Siemens Martin, High Strength and Extra-high Strength. A Utilities grade strand is also made to meet special requirements

Graft copolymer
A copolymer that is a graft polymer. In a graft copolymer, adjacent blocks are constitutionally different, i.e., each of these blocks comprises constitutional units derived from different characteristic species of monomer or with different composition or sequence distribution of constitutional units. (IUPAC)

Graft macromolecule
A macromolecule with one or more species of block connected to the main chain as side chains, these side chains having constitutional or configurational features that differ from those in the main chain. (IUPAC)

Graft polymer
A substance composed of graft macromolecules. (IUPAC)

Green strength
This refers to the relative cohesive strength an adhesive, glue, or mastic has in the wet state. Same as green grab or initial tack. See also tack.

Greenfield
Network deployment in an area under development. Since everything is being built for the first time, network construction can be done with few obstructions and installation can be accomplished parallel to other utilities.

Grid Spaced
When contacts in a multiple contact connector are spaced in a geometric pattern. (MIL-STD)

Grommet
A rubber seal used on the cable side of multiple contact connector to seal the connector against moisture, dirt or air.

Grommet Connector
An elastomeric seal used on the cable side of a connector to seal the connector against moisture, dirt and air. (MIL-STD)

Grooved Drum
Drum with grooved surface to accommodate and guide the rope

Grooves
Depressions in the periphery of a sheave or drum for positioning and supporting a rope

Gross Tonnage and Net Tonnage
The Ship Measurement Convention of 1969 has been in force for new tonnage since 1984, and was made mandatory for all vessels from 18th July 1994. This means a transition from the terms gross register tons (grt)and net register tons (nrt) to gross tons (GT) and net tons (NT). The gross tonnage forms the basis for manning regulations, safety rules and registration fees. Both gross and net tonnage are used to calculate port dues. GT is the vessel's enclosed spaces, while NT is the volume of a vessel's cargo holds.

Ground
1) The connection between an electrical circuit and the earth or other large conducting body to serve as an earth thus making a complete electrical circuit.  2) A conducting connection between an electrical circuit and the earth or other large conducting body to serve as an earth, making a complete electrical circuit.  3) A common voltage reference point, such as chassis or earth.

Ground Conductor
A conductor in a transmission cable or line that is grounded. An electrical conductor for the connection to the earth, making a complete electrical circuit.

Ground Fault
A failure of transmission involving insulation-to-shield or insulation-to-ground wire.

Ground Insulation
The insulation used between a winding and the magnetic core or other structural parts, usually at ground potential.

Ground Loop
A completed circuit between shielded pairs of a multiple pair created by random contact between shields. An undesirable circuit condition in which interference is created by ground currents when grounds are connected at more than one point.

Ground Plane
Expanded copper mesh which is laminated onto some flat cable constructions as a shield.

Ground Potential
Zero potential with respect to the ground or earth.

Ground Power Cable
A cable assembly fitted with appropriate terminations to supply power to an aircraft from ground power unit.

Ground-Fault Circuit-Interrupter
GFCI – Ground-Fault Circuit-Interrupter. An electrical wiring device that disconnects a circuit whenever it detects that the electric current is not balanced between the energized conductor and the return neutral conductor. Such an imbalance is sometimes caused by current leakage through the body of a person who is grounded and accidentally touching the energized part of the circuit.

Grounding Conductor
A conductor which provides a current return path from an electrical device to ground.

Grounding Fingers
A set of spring ingers provided in the connector to allow shell to shell grounding, before contacts mate and after they separate.

Group delay (GD)
The difference in arrival time between wavelengths.

Guard Rail Cable
A galvanized wire rope or strand erected along a highway

GUI
Pronounced "gooey", it�s the abbreviation for Graphical User Interface.

Guide Pin
A pin or rod extending beyond the mating faces of a connector designed to guide the closing or mating of the connector to ensure proper engagement of contacts. (MIL-STD)

Gum
Any of a class of colloidal substances, exuded by or prepared from plants, sticky when moist, composed of complex carbohydrates and organic acids, which are soluble or swell in water.

Guy Line
Strand or rope, usually galvanized, for holding a structure in position

Halar
A trade name of Allied Chemical for their copolymer of ethylene and chlorotrifluor-ethylene. Abbreviation ECTFE.

Half Duplex
A telecommunications device allowing two-way transmission of signals or other information, but only in one direction at a time. Thus a half-duplex device cannot simultaneously transmit and receive, though interspersed bursts in each direction are possible.

Half Duplex Transmission
1) Data transmission over a circuit capable of transmitting in either direction, but only one direction at a time.  2) Mode of operation between two communications devices where only one of them can send or receive at a time.

Halogen
A term used to identify any of the four elements chlorine, fluorine, bromine and iodine, grouped together because their chemical properties are similar.

Halogen Rating
Identifies if a thermoplatic polymer, elastomer, or thermoset rubber has or contains halogen elements. Halogen is an electro-negative atomic element which, if combined with a metal, forms a haloid salt. Halogens are chloride, fluorine, bromine, iodine and astatine. Halogen containing compounds, if exposed to flame, produce corrosive and potentially toxic fumes. Materials can be identified as either halogen-gree or as halogenated.

Halogen-Free
A designation for gases produced during flame and burning of materials or cables. Halogen-free materials do not release potentially toxic chlorine or fluorine gasses. Toxicity of gases under flame and burning conditions is a factor in persons' survivability. There is a test methodology for toxicity which is CTI and the test method is UTE C 20.

Handhole
An access opening provided in equipment or in a below-the-surface enclosure into which personnel reach, but do not enter, to work with or place cable. Also known as maintenance access handhole.

Handoff
Cellular systems are designed so that a phone call can be initiated while driving in one cell and continued as more cells are driven through. The transfer to a new cell is called the handoff and is designed to be transparent to the cellular phone user. This handoff is achieved by network computers which assign the call to another tower just as the user passes from one cell to another, ensuring continuous service.

Handshaking
Exchange of predetermined signals when a connection is established between two data set devices.

Hard Clad Silica (Fiber Optic)
Abbreviated HCS, it is a structure in fibers where the cladding around the glass core is a hard plastic, as opposed to a "PCS," which is a soft plastic cladding.

Hard Conversion
The process of changing a measurement from inch-pound units to nonequivalent metric units that necessitates physical configuration changes outside those permitted by established measurement tolerances. See Soft Conversion

Hard Cure, AL-33xx Series
ÅngströmLink® hard materials with Shore D durometer. All are suited to making thin films for use in PCB optical waveguides, microlens arrays, prism films, or low dielectric layers. Can be applied by spin coating. Compatible with CMOS substrates and fabrication techniques. Excellent adhesion and chemical resistance.

Hard Drawn
Refers to metal that has not been annealed.

Hard Drawn Copper Wire
Copper wire that has been drawn to size and not annealed.

Hardener
A substance or mixture of substances added to an adhesive to promote or control the curing reaction by taking part in it. The term is also used to designate a substance added to control the degree of hardness of the cured fill. Same as curing agent. See also catalyst.

Hardness
A general term that correlates with strength, rigidity and resistance to abrasion or penetration. Measured on Shoer or Rockwell scales.

Hardware
A generic term describing all computing and peripheral machinery.

Hardwire
A permanent connection between two devices, usually not easily disconnected.

Harmonica
A cable adapter used to change an Amphenol type 50 pin Telco connector into multiple RJ-45’s or RJ-11’s.

Harmonized Code
An international coding system for specifying the attributes of cord voltages, jackets, diameters, etc.

Harness
1)An arrangement of wires and cables, usually with many breakouts, which have been tied together or pulled into a rubber or plastic sheath, used to interconnect electric circuits.  2)A group of wires or cables routed together with attached connectors and components, secured to provide a pre-shaped electrical wire or cable assembly.

Harness , Indoor use
(Also Cable) Product intended and designed for indoor use only.

Harness , Outdoor use
(Also Cable) Outdoor Use Cables/Harnesses: Product expected to withstand exposure to he elements of weather.

Harnessing Devices
Tying tapes, lacing cords, and flexible sleevings which are used for wire and cable bundling, harnessing, and holding. Other devices include plastic ties or clamps, spiral-cut plastic tubing, and plastic U-shaped trays or ducts.

Hash Mark Stripe
A non-continuous helical stripe applied to a conductor for identification.

Hazardous Location
Ignitable vapors, dust, or fibers that may cause fire or explosion as defined by the NEC.

Head Assembly
A positioner designed to attach to a crimping tool in place of a turret head. (MIL-STD)

Headend
The point in a LAN where the inbound signals are transferred into outbound signals. The headend may be passive or contain an amplifier or frequency translation equipment. Used in broadband LANs and CATV.

Heat Activated Adhesive
A type of adhesive pre-applied to one or both adherends, that is rendered tacky by application of heat and forms a bond on cooling.

Heat Aging
Strength measured at room temperature after some period of aging at elevated temperature.

Heat Distortion
Distortion of flow of a material or configuration due to the application of heat.

Heat Endurance
The time of heat aging that a material can withstand before failing a specific physical or electrical test.

Heat Seal
In cabling, a method of sealing a tape wrap jacket by means of thermal fusion.

Heat Shock
Test to determine the stability of a material when exposed to a sudden high temperature change for a short period of time.

Heat Shrinkable
A polymeric material capable of being reduced in size when exposed to heat.

Heat Treating
A process that uses precise heating and tooling of metals after stamping and forming in order to optimize internal stresses and spring properties.

Heater Cord
Flexible stranded copper conductor, cotton wrapped with rubber insulation and asbestos roving .

Heel Bead
The ability of a tape to with_stand exposure to specified temperatures after applica_tion to a surface. Clean removal after exposure may or may not be important depending on the intended func_tion of the tape and the type of adhesive.

Helical Stripe
A continuous, colored, spiral stripe applied over the outer perimeter of an insulated conductor for circuit identification purposes.

Helix
Spiral winding.

Henry (H)
The standard unit of inductance. The inductance of a current is a one Henry when a current variation of one ampere per second induces one volt.

Hermaphroditic Connector
A connector design which utilized pin and socket contacts in a balanced arrangement such that both mating connectors are identical. The contacts may also be hermaphroditic and may be arranged as male and female contacts as for pins and sockets. Hermaphroditic contacts may also be used in a manner such that one half of each contact mating surface protrudes beyond the connector interface and both mating connectors are identical (MIL-STD)

Hermaphroditic Contact
A contact design which is a combination pin and socket and which mates with other contacts of the same design. (MIL-STD) Both mating elements are precisely alike at their mating face

Hermetic
Permanently sealed by fusion, soldering, or other means to prevent the transmission of air, moisture vapor, and all other gases. Hermeticity is usually expressed as the rate of leakage volume of tracer gas (such as helium) per second in time.

Hermetic Seal
Connector contacts are bonded to the connector by glass or other materials which permit maximum leakage rate of gas through the connector of 1.0 micron ft./hr. at one atmosphere pressure for special applications.

Hermetically Sealed
A gas-tight enclosure that has been completely sealed by fusion or other comparable means.

Hertz
Unit of measure of frequency of alternating current. One hertz is equal to one cycle per second.

Heterogeneous Insulation
A cable insulating system composed of two or more layers of different insulating materials.

Hi-pot
A test designed to determine the highest potential that can be applied to a conductor without breaking through the insulation.

High definition television (HDTV)
Digital television with significantly more resolution than that provided by a good NTSC or PAL television signal. The specific resolution can vary, however it is typically about twice the resolution of standard television signals, and has a wider aspect ratio.

High Frequency (HF)
The band from 3 MHz to 30 MHz in the radio spectrum, as designated by the Federal Communications Commission.

High performance parallel interface (HIPPI)
A system for high-speed supercomputer-to-supercomputer connectivity above 1 Gb/s.

High Strength Alloy Conductor
A conductor which shows a maximum 20% increase in resistance and a minimum of a 70% increase in breaking strength over the equivalent construction in pure copper while exhibiting a minimum elongation of 5% in 10 inches.

High Strength Strand
Grade of galvanized or bright strand

High temperature crossover (TxOver)
Temperature at which an adhesive loses its elastomeric properties and melts to a flowable liquid. This value is a stability indicator for high temperature applications. For example, the higher the value, generally, the more heat stable the product is.

High Temperature Wire and Cable
Electrical wire and cables having thermal operating characteristics of 150°C and higher.

High Voltage (HV)
Cables rated over 35Kv. The National Electrical Code defines any cable over 600 volts as High Voltage for the purposes of Article 710. However, Article 326 delineates the generally accepted parameters of Medium Voltage and High Voltage .

High wire resistance
The expected connection is established but the current is weak due to current being limited as it runs through the connection.

High-density connector
Typically, connectors with multiple fibers in a small form factorhousing, i.e., MPO/MTP, MT-RJ.

High-density polyethylene (HDPE)
A jacketing material used in harsh environments to protect cables from accidental chemical exposure.

High-Lever Data Link Control (HDLC)
The protocol defined by ISO in 1976 for bit-oriented, frame-delimited data communications

High-speed Token Ring (HSTR)
IEEE 802.5J proposed 100 Mb/s.

high-speed unwind
The unwinding or dispensing of tapes at a relatively high rate of speed, usually over 50 feet per minute.

Higher Performance Radio Local-Area Network (HIPERLAN)
HIPERLAN is the European standard for short-range (approx. 50m) high performance radio local-area networks. HIPERLAN operates in the 5.1-to-5.3-GHz band. Another band may be available in the future operating in the 17.1-to-17.3-GHz range, but as of 8/97, specifications have not been finalized.

HiperLAN
High Performance Radio Local Area Network

HiperMAN
High Performance Radio Metropolitan Area network

Holding Strength
Ability of a connector to remain assembled to a cable when under tension.

Holiday
A small defect, particularly in an electrical or pipe wrapping tape, which lowers the dielectric strength at the point of the defect below a certain desired minimum.

Home Location Register
The data base of customer information that makes subscriber information available to a mobile-telephone switching office. The register functions as a network element.

Home Run
A PON architecture where the optical splitter is housed at the service provider’s facility. Home runs are the easiest for handling changes, but require a fiber rich cabling system as one fiber is dedicated for each subscriber. A cable run going from a workstation or office directly back to a wiring closet with no other connections. Physical star topologies consist exclusively of home runs.

HomePNA
Home Phoneline Networking Alliance

Homogeneous Insulation
A complete cable insulation structure whose components cannot be identified as layers of different materials.

Homopolymer
a polymer derived from one species of (real, implicit, or hypothetical) monomer. Note many polymers are made by mutual reaction of complementary monomers. These monomers can readily be visualized as reacting to give an "implicit monomer", the homopolymerization of which would give the actual product, which can then be regarded as a homopolymer. Example poly(ethylene terephthalate). Some polymers are obtained by modification of other polymers such that the structure of the macromolecules that constitute the resulting polymer can be thought of as having been formed by homopolymerization of a "hypothetical monomer". These polymers can be regarded as homopolymers. Example poly(vinyl alcohol). (IUPAC)

Homopolymerization
polymerization in which a homopolymer is formed. (IUPAC)

Hood
An enclosure attached to the back of a connector to contain and protect the wires and cable attached to the terminals of a connector.See also Backshell.

Hook-up Wire
Single conductor used to hook-up electrical parts of instruments for low current and voltage (under 1000 volts).

Horizontal Cable
A cable connecting the floor distributor to the telecommunications outlet(s).

Horizontal Cabling
The wiring/cabling between the telecommunications outlet/connector and the horizontal cross-connect.

Horizontal Cross-Connect (HC)
A cross-connect of horizontal cabling to other cabling, e.g., horizontal, backbone or equipment. Could be a patch panel or LAN (small) panel.

Horizontal Length (HL)
The cable distance from the information outlet to the blue field of the cross connect. In SYSTIMAX� SCS, this is referred to as the Horizontal Subsystem.

Horizontal Runs
The part of the premises distribution system installed on one floor that includes the cabling and distribution components connecting the riser backbone or equipment wiring to the information outlet.

Horizontal Stripe
A colored stripe running horizontally with the axis of a conductor, sometimes called a longitudinal stripe, used as a means of circuit identification.

Horizontal Subsystem
The part of a premises distribution system installed on one floor that includes the cabling and distribution components connecting the Riser backbone Subsystem to the information outlet via cross-connect components of the Administration Subsystem.

Horn Antenna
A microwave antenna made by flaring out the end of a circular or rectangular waveguide in the shape of a horn. It is used for radiating radio waves into space.

HOST
Term describing a Host computer. A central computer responsible for the control of time-share terminals and other peripherals. Usually associated with minicomputers and mainframes.

Host Computer
1) A computer attached to a network providing primarily services such as computation, database access or special programs or programming languages.��2) An information processor which provides supporting services and/or guidance to users and/or satellite processors, terminals and other subsidiary devices. A host processor generally is assumed to be self-sufficient and to require no supervision from other processors.��3) Compare with communications computer.

Hot Dip
A term denoting the covering of a surface by means of dipping the surface to be coated into a molten bath of the coating material.

Hot melt
A type of connector pre-loaded with epoxy. The connector must be heated to liquefy epoxy for fiber optic insertion. The ferrule is then cooled to re-harden the epoxy. Manufactured by 3M.

Hot Stamping
Method of alpha numerical coding. Identification markings are made by pressing heated type and marking foil into softened insulation surfaces. See Surface Printing .

Hot Strength
Strength measured at elevated temperature.

Hot Tin Dip
A process of passing bare wire t h rough a bath of molten tin to provide a coating.

Hot-melt adhesive
A thermoplastic adhesive that is applied in a molten state and forms a bond upon cooling to a solid state.

Hot-setting adhesive
A thermoplastic adhesive that is applied in a molten state and forms a bond upon cooling to a solid state.

Housing
The main or largest portion of a connector to which other portions are attached or enclosed.

Housing Connector
Connectorless insert but with insert retaining and positioning hardware required by standard construction. (MIL-STD)

Hub Activation
Hub activation tests transmit a signal to a 10 BASE-T hub to verify it is operational.

Hub(S)
A concentrator or repeater in a star topology at which node connections meet.

Hum
A term used to describe 60 or 120 cycle sound present in the sound of some communication equipment, usually the result of either undesired coupling to 60 cycle source or defective filtering of 120 cycle rectifier output.

Hum bars
60-Hz signals that appear on coax and consequently on-screen as horizontal lines.

Hybrid
Cable which contains both optical fiber(s) and metallic conductor(s).

Hybrid Cable
An assembly of two or more different types of cable units, cables or categories covered by an overall sheath. It may be covered by an overall shield.

Hybrid Cable Assembly
A jumper assembly with different connections on each end.

Hybrid Fiber Coax (HFC)
A hybrid system, used by the CATV industry, that employs a fiber optic backbone and coax cables for final distribution from the node to the customer.

Hygroscopic
A material capable of absorbing and retaining moisture from the air.

Hypalon®
Dupont's trade name for their chlorosulfonated polyethylene, an ozone resistant synthetic rubber.

HyperLAN
See HiperLAN

HyperMAN
See HiperMAn

Hysteresis
The lag between a cause and effect; temperature change and resultant electrical phase changes in cable when the temperature returns to the initial point of measurement.

Hz
Hertz

I/O CHANNEL
A high-speed bus used to interconnect peripherals with the CPU.

I/O CONTROLLER
A device that arbitrates the I/O channel and controls data transfer between devices attached to the channel.

I2R
Formula for power in watts, where I = current in amperes, R = resistance in ohms. Also see Watt.

IBM Token Ring
A token passing network topology that conforms to the IEEE 802.5 definition and documents. Operating at 4 Mbps or 16 Mbps, it is the chief topology used to interconnect small and mid-size equipment from IBM and other vendors.

IEEE
Abbreviation of the Institute of Electrical and Electronics Engineers or IEEE (pronounced as eye-triple-e) is an international organization for the advancement of technology related to electricity. 

IEEE 1394
FireWire (of Firewire) standard

IEEE 802
IEEE committee to develop LAN standards

IEEE 802.11
Designation for the IEEE subcommittee which is developing the wireless local-area network standard. This standard is being formulated to provide interoperability of wireless local-area-network products.

IEEE 802.3
Ethernet standards

IEEE 802.X
Guidelines describing the physical and data link layers of the OSI network model for various topologies.

IEEE Project 802
An IEEE standards development project concerned with LANs.

Ignition Cable
Cable designed for Automotive Ignition Systems.

IL
Insertion Loss.

IL/RL
Insertion Loss / Return Loss.

IM /PIM (Passive Intermodulation)
The generation of new, and in the case of cable assemblies, undesirable signals called intermodulation products, at the non-linear characteristics of transmission elements

Impact resistance
A test that determines the ability of fiber optic cables and cable assemblies to withstand repeated impact loads. It measures the number of broken fibers, damage to the outer sheath, and any change in the optical transmittance or attenuation. Specified in the TIA/EIA 455-25 “Repeated Impact testing of Fiber Optic Cables and Cable Assemblies” fiber optic test procedure.

impact resistance (shock resistance)
The ability of a tape to resist sudden pulls or shocks as may some_times be encountered by packages in transit.

Impact Strength
Test for ascertaining the punishment a cable configuration can withstand without physical or electrical breakdown, by impacting with a given weight, dropped a given distance in a controlled environment.

Impact Tool
Device used to punch new conductor onto ID's. This tool is typically equipped with a cutting blade for either 66 or 110 blocks.

Impedance (Z)
The total opposition that a circuit offers to the flow of alternating current or any other varying current at a particular frequency. It is a combination of resistance R and reactance X, measured in ohms. Resistance to flow of an alternating current at a particular frequency, expressed in ohms. It is a combination of resistance R and reactance X, measured in ohms.

Impedance Match
A condition in which the impedance of a particular circuit cable or component is the same as the impedance of the circuit, cable or device to which it is connected.

Impedance Matching
Connecting cables and devices together which have the same impedance value in ohms.

Impedance Matching Stub
A section of transmission line or pair of conductors cut to match the impedance of a load. Also called matching stub.

Impedance Matching Transformer
A transformer designed to match the impedance of one circuit to that of another.

Impedance, Characteristic
In a transmission cable of infinite length, the ratio of the applied voltage to the resultant current at the point the voltage is applied. Or the impedance which makes a transmission cable seem infinitely long, when connected across the cable’s output terminals.

Impregnate
To fill the voids and interstices of cable or the fabric of a cable with a compound.

Improved Plow
See "Grades, Rope"

Impulse
A surge of unidirectional polarity

Impulse Noise
Intermittent, short, high frequency, high amplitude pulses that are induced into a transmission line. Can cause data corruption and in some cases hardware damage.

Impulse Strength
The voltage breakdown of insulation under voltage surges on the order of microseconds in duration.

Impulse Test
An insulation test in which the voltage applied is an impulse voltage of specified wave shape.

Incoherent Source
A light source which emits wide, diffuse beams of light of many wave lengths.

Incumbent local exchange carrier (ILEC)
The dominant phone carrier within a geographic area that provides local exchange service to that area.

Indentor
The part of a crimping die, usually the moving part, which indents or compresses the contact barrel. (MIL-STD)

Independent Wire Rope Core
Wire rope used as the core of a larger rope

Index matching fluid
A liquid used of refractive index similar to glass used to match the materials at the ends of two fibers to reduce loss and back reflection.

Index of Refraction (IR)
The ratio of the speed of light in a vacuum to the speed of light in a material. When light strikes the surface of a transparent material, some light is reflected while some is bent (refracted) as it enters. The IR is used to calibrate OTDRs for measuring fiber length.

Index Profile
A graded-index optical fiber, the refractive index as a function of radius.

Indirect Lightning Effects
Refers to the damage to or malfunction of electronic systems that results from a nearby lightning discharge.

Indium gallium arsenide (InGaAs)
The components of crystalline semiconductors used in fiber optic photodetectors.

Individual Pair Screened
Where each twisted pair in one overall cable has its own screen.

Induced Current
An electric current set up in a circuit by cutting lines of force; a current caused by electromagnetic induction.

Inductance
The property of a circuit or circuit element that opposes a change in current flow, thus causing current changes to lag behind voltage changes. It is measured in Henrys.

Induction
An influence exerted by a charged body or by a magnetic field on adjacent bodies without apparent communication.

Induction Heating
Heating a conducting material by placing it in a rapidly changing magnetic field. The changing field induces electric currents in the material and I2R losses account for the resultant heat.

Inductive Coupling
Crosstalk resulting from the action of the electromagnetic field of one conductor on the other.

Industrial Scientific Medical
The unlicensed radio band in North America and some European countries. Also referred to as Part 15.247, this FCC regulation defines the parameters for use of the ISM bands in the US, including power output, spread spectrum, and non-interference. The commonly used ISM bands include 902-to-928-MHz, 2400-to-2483-MHz and 5725-to-5850-MHz.

InfiniBand Architecture
A high bandwidth switched network topology currently being developed for Storage Area Networks (SANS).

Infrared
Light wavelengths extending from 770 nm on.

Infrared (Fiber Optic)
Light with wavelengths 700-1000 nm, invisible to the eye, and felt as heat.

Infrared (IR)
The range of electromagnetic wavelengths between the visible part of the spectrum (750 nm) and microwaves (30 µm).

Infrastructure Equipment
The fixed transmitting and receiving equipment in a communications system. This usually consists of base station, base station controllers, antennas, switches, management information systems and any other equipment that makes up a system which sends and receives signals from mobile or handheld subscriber equipment and/or the public-switched telephone network.

Infrastructure, Telecommunications
A collection of those telecommunications components, excluding equipment, that together provide the basic support for the distribution of all information within a building or campus.

Inherent viscosity/logarithmic viscosity number
The ratio of the natural logarithm of the relative viscosity to the mass concentration of the polymer. (IUPAC)

Inhibitor
A substance used to suppress a chemical reaction.

initiation
The first step in addition polymerization in which a highly reactive species is generated, usually a free radical

Injection Laser Diode (ILD)
A laser in which the lasing occurs at the junction of n-type semiconductor materials. Sometimes called a diode laser.

Inlet
A male flange mounted wiring device with the conducting pins protruding and exposed. This type device should never be wired to make the exposed pins live while the mating device is unplugged.

Inline splice closure
Closure that has cable ports at opposite ends.

Inmarsat
International Maritime Satellite System

Inner Conductor
The central conductive member in a coaxial structure, such as the center contact in a coaxial connector.

Innerduct
Usually a nonmetallic pathway that may be placed within a duct to facilitate initial and subsequent placement of multiple cables in a single duct.

Input
A signal (or power) which is applied to a piece of electric apparatus or the terminals on the apparatus to which a signal or power is applied.

Input/Output (I/O)
The machine or device used to insert information, data or instructions into a computing system or the medium or device used to transfer information or data, usually processed data, from a computing system to the outside world. Input/output also can refer to the act of entering or retrieving information.

Insert
That part which holds the contacts in their proper arrangement and electrically insulates them from each other and from the shell.

Insert Arrangement
The number, spacing and arrangement of contacts in a connector.

Insert Cavity
A defined hole in the connector insert into which the contacts are inserted.

Insert Electrical Connector
An insulating element with or without contacts designed to position and support contacts in a connector. (MIL-STD

Insert Retention
Axial load in either direction that na insert must withstand without being dislocated from its normal poition in the connector shell.

Insert Retention Force
The maximum allowable force which, if applied to the mating face of a connector insert, does not displace the insert permanently from its normal position in the connector housing or jeopardize or damage the insert or connector housing retention provision.

Insert, Connector
The element that holds connector contacts in their proper arrangement and electrically insulates the contacts from one another and from the connector shell.

Insertion Force
The effort, usually measured in ounces, required to engage mating components.

Insertion Loss
The ratio between the power received at a specified load before and after the insertion of a filter at a given frequency. It is an indication of the attenuation provided by a filter.

Insertion Tool
A small, hand-held tool used tto insert contacts into a connector.

Inside Plant (ISP)
All cable and equipment inside a central office or subscriber's premises.

Inside Wire
Wire designed to carry a telephone circuit(s) through the customer's premises.

Inspection Gage
A device which conforms to the gaging limits specified on the applicable tool specification sheet.

Inspection Hole
A hole placed at one end of a crimp contact barrel to insure proper insertion of the conductor prior to crimping. (MIL-STD)

Inspection scope
A microscope or digital scope that inspects ferrule and termini fiber endfaces for polishing quality, damage, or contamination.

Installation Tool
A device used to install contacts into a connector. A device used to install taper pins into taper pin receptacles.

Institute of Electrical and Electronics Engineers (IEEE)
A standards organization representing the United States on the ISO in the areas of electrical or electronic standards. Writes standards on communications including Ethernet and OPGW and ADSS cables.

Insulated Terminal
A solderless terminal with an insulated sleeve over the barrel to prevent a short circuit in certain installations.

Insulated Wire
A conductor of electricity covered with a non-conducting material.

Insulating Joint
A device which mechanically couples and electrically insulates the sheath and armor of contiguous lengths of cable.

Insulation
1) A material which offers high electrical resistance making it suitable for covering components, terminals and wires to prevent the possible future contact of the adjacent conductors resulting in a short circuit. This is often called a dielectric.  2) A material having high resistance to the flow of electric current.

Insulation Adhesion
The degree of tightness of the insulation over the base conductor, measured in terms of force required to remove a specified length of insulation from the wire.

Insulation Adhesive
The degree of tightness of the insulation over the base conductor, measured in terms of force required to remove a specified length of insulation from the wire.

Insulation Conductor
A non-metallic covering applied around a metallic conductor or optical fiber to provide electrical isolation and/or moisture protection.

Insulation Crimp
Area of a terminal, splice or contact that has been formed aroind the insulation of the wire.

Insulation Crip
An extended cylinder at the rear of a contact designed to accept the bared wire and a small length of its insulation. When crimped, both the wire and insulation are held firmly in place.

Insulation Displacement
The type of wire terminals that require no wire stripping; when the wire is correctly attached, its insulation is displaced (pierced) to form a connection.

Insulation Displacement Connector (IDC)
An assembly process wherein an insulation piercing edge of the contact is pushed through the insulation and into contact with the wire by the assembly press. Most commonly used in mass termination applications. A mass termination connector for flat cable with contacts that displace the conductor insulation to establish simultaneous contact with all conductors.

Insulation Grip
Extended cylinders at the rear of crimp-type contacts designed to accept the bared wire and a small length of its insulation.

Insulation Level
A designation used to identify the insulation thickness required to protect a high voltage cable under ground fault conditions. Expressed as a percentage (e.g. 100% level, 133% level).

Insulation Piercing
A method of crimping whereby lances cut the insulation of the wires and enter into the strands to make electrical contact.

Insulation Resistance
The electrical resistance of the insulating material (determined under specified conditions) between any pair of contacts, conductors, or grounding device in various combinations.

Insulation Resistance (IR) failure
Insulation fails to properly separate points at a required level. The insulation resistance is sufficient to prevent a short, yet is not high enough to meet the insulation resistance specification.

Insulation Shield (HV Cable)
A two part shield consisting of a non-metallic component and a metallic component. The first component is an extrusion of black semi-conducting thermoset material over the insulation which provides uniform radial stress distribution across the insulation.

Insulation Stress
High voltage stress which causes molecular separation in the insulation at sharp projections in the conductor. Controlled by conductor and insulation shielding, called a stress relief shield. Measured in volts per mil. The molecule separation pressure caused by a potential difference across an insulator. The practical stress on insulation is expressed in volts per mil.

Insulation Support
The portion of a barrel similar to an insulation grip except that it is not compressed around the conductor insulation. (MIL-STD)

Insulation System
All of the insulation materials used to insulate a particular electrical or electronic product.

Insulation Thickness
The wall thickness of the applied insulation.

Insulator
A material such as ceramic, rubber, or plastic that blocks the flow of electric current. An insulator is a poor conductor because it has a high resistance to such flow. 

Integral Belt
A layer of insulation or semi-conductive material applied by extrusion over two or more insulated, twisted or parallel conductors, to form a round smooth diameter.

Integrated Circuit
A microscopic array of electronic circuits and components that has been implanted onto the surface of a single crystal, or chip, of semiconducting material such as silicon. It is called an integrated circuit because the components, circuits, and base material are all made together, or integrated, out of a single piece of silicon. An integrated circuit is commonly referred to as an IC. 

Integrated Services Digital Network (ISDN)
Integrated voice and data network based on digital communications technology and standards interfaces.

Integrating Sphere
Optical mixing chamber fitted to Detector, allowing use multi-channel connectors like MPO.

Intelligent Buildings
Buildings that maximize the efficiency of its occupants and allow effective management of resources with minimum life-time costs (Source: European Intelligent Building Group).

Intelligent Peripheral Interface (IPI)
Links peripheral (subordinate) devices to host or master.

Intelligent Terminals
A terminal which contains an integral microprocessor with some logical capability.

Intensity
Irradiance.

Inter-Mateable
Characteristic of connectors in which a connector half of one manufacturer will mate directly with a connector half manufactured by a different company.

Interaxial Spacing
1) Center to center conductor spacing is paired wire or  2) center to center spacing between conductors in a flat cable.

Interbuilding
Between buildings.

Interbuilding backbone
A network that provides communications between buildings, e.g., college campus, office park, or military installation.

Interchangeable
Characteristic of connectors in which one manufacturer's connector can be replaced by one of another manufacturer and provide the same function in the same panel space as the connector it replaced.

Intercloset Cables
Cables that connect telecommunications closets.

Interconnect
A connection scheme that provides for the direct connection of individual cables to another cable or to an equipment cable without a patch cord.

Interconnect Companies
Companies which sell, install and maintain telephone systems for end users.

Interconnecting Cable
The wiring between modules, between units, or the larger portions of a system.

Interconnecting Wire
The physical wiring between components (outside a module) between modules, between units or between larger portions of a system or systems.

Interconnection
Mechanically joining devices together to complete an electrical circuit.

Interexchange carrier (IXC)
Any common carrier that provides long-distance services, i.e., Sprint or AT&T.

Interface
1) Shared boundary defined by common physical interconnection characteristics (often including a connector), signal characteristics and meanings of interchanged signals.  2) A device or equipment making inter-operation of two systems possible; for example, a hardware component or common storage register.  3)The two surfaces on the contact side of a mating connector or plug-in component (e.g. relay) and receptacle, which face each other when mated. (MIL-STD)

Interface Cards
See Network Interface Cards.

Interfacial Compression
The compression of the resilient material which faces the mating inserts and provides positive sealing and insulation when plug and receptacle are fully engaged or mated.

Interfacial Gap
Any space between the faces of mated connectors.

Interfacial Seal
A sealing of mated connectors over the whole area of the interface to provide sealing around each contact. (MIL-STD)

Interference
Any to electrical signal induced into a conductor by electrical or electro-magnetic means. A signal impairment caused by the interaction of another unwanted signal. Electrical or electromagnetic disturbances which introduce undesirable responses into other electronic equipment. Disturbances of an electrical or electromagnetic nature that introduce undesirable responses into other electronic equipment.

Interference bands
Measured on an interferometer, the dark lines or “bands” optically projected across the face of an object to determine its shape by means of measured elevation.

Interferometer
A measurement instrument that projects interference bands across the face of fiber optic connector. The bands are used to determine the centering, angle of apex offset and radius of curvature of the fiber optic connector.

Intermediate Cross-Connect (IC)
A cross connect between first and second level backbone cabling. It can be between main (MC) and horizontal (HC). Normally would consist of a patch panel.

Intermediate distribution frame (IDF)
A metal rack located in an equipment room or closet that is designed to connect cables. It consists of components that provide the connection between interbuilding cabling and the intrabuilding cabling.

Intermediate Frequency
A frequency to which a signal is converted for ease of handling. Receives its name from the fact that it is an intermediate step between the initial and final conversion or detection stages.

intermediate-temperature-setting adhesive
An adhesive that sets in the temperature range from 31 to 99°C (87 to 211°F).

Intermetallic
Chemical compounds formed between the metals present in the solder, base metal and protective platings. Intermetallic formation is necessary for good solder joints, but excessive intermetalics can cause brittleness.

Intermittent open
The intended electrical path contains an unintended gap that appears and disappears when the assembly is flexed.

Intermittent short
An unintended connection between 2 or more parts which appears and disappears when the assembly is flexed.

Intermodulation Distortion(IMD)
A phenomenon that occurs when two or more fundamental frequencies are present in an electronic circuit and produce spurious signals that are sum and differences of the fundamental frequencies.

Internal Wiring
Electronic wiring which interconnects components, usually within a sealed subsystem.

Internally Lubricated
Wire rope or strand having all wires coated with lubricant

International Electrotechnical Commission (IEC)
An international standards body responsible for a wide range of recommendations and standards for telecommunications.

International Standards Organization (ISO)
The organization responsible for the Open Systems Interconnect (OSI) standards. International Standards Organization.

International Telecommunications Union (ITU)
The international body for communications standards. The telecommunications group within ITU is designated as ITU-T.

International Telegraphy and Telephone Consultative Committee (CCITT)
A standards organization that, among numerous other activities, specializes in the electrical and functional characteristics of switching equipment. The CCITT sets standards for interfaces to ensure compatibility between data communications equipment (DCE) and date terminating equipment (DTE).

Internet protocol (IP)
A set of rules for how data is transmitted from place to place on the Internet. IP is a connectionless protocol in which data is broken down into small bundles known as packets. Each packet is transmitted separately, possibly along a different route than other packets from the same message.

Internet protocol address
A protocol on which the Internet is based, this software describing standard tracks addresses for different nodes, routes outgoing messages, and recognizes incoming messages.

Internet protocol television (IPTV)
A compressed digitized video provided through packet or cell transmission (FTTH) to subscribers.

Internet service provider (ISP)
An organization whose business is connecting users to the Internet. By serving as the interface between end users and the Internet, the ISP’s equipment is analogous to a CATV head end or telephony CO.

Internetworking
The connection of multiple networks for data interchange. This is normally accomplished with interface devices such as bridges, brouters and gateways.

InterNIC
Internet Network Information Center

Interoperability
The ability to operate and exchange information in a heterogeneous network.

Interphase
In an adhesive joint, a region of finite dimension extending from a point in the adherend where the local properties (chemical, physical, mechanical, and morphological) begin to change from the bulk properties of the adherend to a point in the adhesive where the local properties equal the bulk properties of the adhesive.

Interstice
In cable construction, the space, valley or void left between or around the cable components.

Interstices
Voids or valleys between individual strands in a conductor or between insulated conductors in a multiconductor cable. Space between adjacent structures.

Intrabuilding
Within a building.

Intrabuilding backbone
A network that provides communications within a building; often referred to as the riser backbone in vertical buildings.

Intrinsic losses
Losses arising from differences in fiber tolerances.

intrinsic viscosity/limiting viscosity number
The limiting value of the reduced viscosity or the inherent viscosity at infinite dilution of the polymer. (IUPAC)

Ionic copolymerization
A copolymerization which is an ionic polymerization. (IUPAC)

Ionic polymerization
A chain polymerization in which the kinetic-chain carriers are ions. Usually, the growing chain ends are ions. (IUPAC)

Ionization
The formation of ions. Ions are produced when polar compounds are dissolved in a solvent and when a liquid, gas or solid is caused to lose or gain electrons due to the passage of an electric current.

Ionization Voltage
The potential at which a material ionizes. The potential at which an atom gives up an electron.

Ionization Voltage (Corona Level)
The minimum value of falling rms voltage which sustains electrical discharge within the vacuous or gas filled spaces in the cable construction or insulation.

Ionomer molecule
A polyelectrolyte in which a small but significant proportion of the constitutional units carry charges. (IUPAC)

IPC
A worldwide organization that sets standards, specifications and guidelines for PCB design, manufacture and assembly. 

IR Drop
The designation of a voltage drop in terms of current and resistance.

IR Reflow
A soldering process that uses infrared (IR) light with a wavelength between visible light and microwave radiation as its energy source.

IR Shadowing
When connector bodies or other components prevent the infrared energy from directly striking some solder joints, causing non-uniform heading.

IRE or IEEE Units
An industry measurement of 100 IRE or IEEE units equals one volt of video.

Iridium Mobile
Satellite phone/pager network launched November 1998

Iron-Constantan
A combination of metals used in thermocouples, thermocouple wires and thermocouple lead wires. Constantan is an alloy of copper, nickel, manganese and iron. The iron wire is positive, the constantan is negative.

Irradiated
Exposure to high-energy radiation resulting in cross-linking of molecules.

Irradiation
The process of cross linking the insulation. In insulations, the exposure of the material to high energy emissions for the purpose of favorably altering the molecular structure by crosslinking.

Irregular macromolecule
A macromolecule in which the constitutional units are not all identical. (IUPAC)

Irregular polymer
A substance composed of irregular macromolecules. (IUPAC)

ISDN (Integrated Service Digital Network)
A digital data communications network providing full integration of data, voice and video.

ISO 7776
ISO’s High-Level Data Link Control Procedures X.25

ISO 8280
ISO’s X.25 Packet Level Protocol for DTE

ISO 9001
ISO’s rigorous international quality standard covering a company’s R&D, design, production, installation, and service procedures.

ISO Seven Layer Model
A 7 layer hierarchical reference structure developed by the ISO for defining, specifying and relating communications protocol.

ISO/IEC 11801
International standard ISO/IEC 11801 Information technology — Generic cabling for customer premises specifies general-purpose telecommunication cabling systems (structured cabling) that are suitable for a wide range of applications (analog and ISDN telephony, various data communication standards, building control systems, factory automation). It covers both balanced copper cabling and optical fibre cabling. The standard was designed for use within commercial premises that may consist of either a single building or of multiple buildings on a campus. It was optimized for premises that span up to 3 km, up to 1 km² office space, with between 50 and 50,000 persons, but can also be applied for installations outside this range.

ISO/IEC 14763-1
The international standard for basic administration of generic cabling.

ISO/IEC IS 11801
An international standard for generic cabling for customer premises.

Isochronous
The delivery of fixed length units of information at fixed time intervals relative to a time reference.

Isochronous Ethernet
This is part of the IEEE 802.9 integrated services LAN standard. It is an extension of 10Base-T which provides for the inclusion of a 6.144 Mbps isochronous (real time and delay sensitive) data service in addition to the 10 Mb/s 10BaseT packet service. It will provide multimedia capability.

Isolation
The ability of a circuit or component to reject interference, usually expressed in dB.

Isolator
A passive fiber optic component that either allows only unidirectional passing of light or that passes only some wavelengths of light. Used in conjunction with lasers or optical amplifiers to reduce or remove backreflections.

Isotactic macromolecule
A macromolecule comprising only one species of configurational base unit (having chiral or prochiral atoms in the main chain) in a single arrangement with respect to its adjacent constitutional units. Note in an isotactic macromolecule, the configurational repeating unit is identical with the configurational base unit. (IUPAC)

Isotactic polymer
A substance composed of isotactic macromolecules. (IUPAC)

ISTEL92
See ETIS

J1, (and if fitted) J2
Laser source outputs, SM or MM.

Jabbering, Jabber
The continuous transmission of meaningless data, usually due to a failure of some sort. The network slows tremendously when burdened with this excess traffic.

Jack
A receptacle used with a plug to make electrical contact between communications circuits. Jacks and their associated plugs are used in a variety of connecting hardware applications including adapter, information outlets, and equipment connections. A connecting device into which a plug can be inserted to make circuit connections. The jack may also have contacts which open or close to perform switching functions when the plug is inserted or removed. See also: receptacle.

Jacket
1)An outer covering, usually non-metallic, mainly used for protection against the environment.  2)The outermost layer of insulating material of a cable or wire. (MIL-STD)

Jacketing
The outer jacket of a cable, which can be made from a variety of materials including but not limited to HDPE, MDPE, PVC, et. al.

Jackscrew
A screw attached to one half of a two-piece, multiple-contact connector and used to draw both halves together and to separate them.

Jackscrew (Screwlock)
A screw attached to one half of a two-piece multiple contact connector used to draw and hold both halves together and to separate them. (MIL-STD)

JAN Specification
Joint Army-Navy specification (replaced by current Military Specifications).

Japan Digital Cellular (JDC)
A digital cellular standard developed by NTT of Japan, operating in Japan at 800 and 1500 MHz.

Joint conditioning time
The time interval between the removal of the joint from the conditions of heat or pressure, or both, used to accomplish bonding and the attainment of approximately maximum bond strength.

Joule (J)
A unit of work or energy equal to 0.7375 foot-pounds. A joule is a measurement of energy. The joule rating on a surge protector indicates the amount of energy that a device is capable of absorbing. In general, the higher the joule rating, the better the unit is able to protect equipment.

Jumper
An assembly of twisted pairs without connectors used to join telecommunications circuits/links at the cross-connect. In fiber optic cable the cable that has connectors terminated on both ends.

Jumper Cable
1) A short flat cable interconnecting two wiring boards or devices.  2) A coaxial cable terminated at each end with a coaxial connector and used to interconnect two electronic devices.

Jumper Wire
A short length of Connectorized copper wire used to route a circuit by linking two cross-connect termination points. PVC insulated connectors twisted together and used for cross-connecting on distributing frames.

Junction
A point in a circuit where two or more wires are connected.

Jute
A natural fiber of plant base formed into rope-like strands. Used in cables for filling the interstices to give a round cross-section.

JvNCnet
Jon von Neumann Computer Network

K-Band
Radio spectrum in the 18GHz to 27GHz range used by satellite communications systems.

Ka-Band
Radio spectrum in the 27GHz to 40GHz range used by satellite communications systems.

Kapton
DuPont® Company registered trademark for Polyimide film.

Kaying
Mechanical arrangement of guide pins and sockets, keying plugs, contacts, bosses, slots, keyways, inserts or grooves in a connector housing shell or insert that allows connectors or the same size and typw to be lined up without the danger of making a wrong connection.

Kellems grip
Wire, aramid or synthetic mesh that is placed around the cable to be installed, intended to provide positive pulling power. Also known as pulling or mesh grips.

Kevlar™
DuPont trade name for aramid material (see Aramid Yarn).

Key
A short pin or other projection which slides in a mating slot or groove to guide two parts being assembled. Generally used in round, shell-enclosed connectors to prevent mating wrong connectors and to assist in polarization.

Keyed
Connectors in which the plug and adaptor are fixed in alignment to prevent rotation and physical fiber endface damage.

Keying
Mechanical arrangement of keyways, inserts or grooves in a connector shell or insert that allows connectors of the same configuration to be used without the danger of interconnection to the wrong mating connector.

Keying Plug Contact
A component that is inserted into a cavity of a connector housing or inseert to assure engagment of identically matched components.

Keying Signal
The video signal that is used to delete that portion of the background signal that is to be replaced with another video signal.

Keyway
A slot or groove in which a key slides. (MIL-STD)

Kilo (k)
Numerical prefix denoting one thousand.

Kilocycle
A term denoting one thousand cycles. (See Kilohertz)

Kilohertz (Khz)
One thousand cycles per second.

Kilometer (km)
Unit of measure for length equal to 1000 meters and about 3,281 feet.

Kilovolt
1,000 volts

Kilowatt
1,000 watts

Kink
Sharp bend in a wire rope that permanently distorts the wires and strands

Kinked
An abrupt bend from which a wire strand is not easily resorted to its original condition.

Kitted
See Consignment. 

Ku-Band
Radio spectrum in the 12 GHz to 18 GHz range used by satellite communication systems.

Kynar®
A Dupont trademark for a fluorocarbon insulation rated -65°C to 135°C.

L-band
The “long” DWDM transmission band, occupying the 1565 nm to 1625 nm wavelength range.

Label stock
Pressure sensitive materials, which are usually printed, frequently die-cut, furnished in roll or sheet form with a liner, and intended for use as labels.

Lacing and Harnessing
A method of grouping wires by securing them in bundles of designated patterns.

Lacing Cord or Twine
Used for tying cable forms, hook-up wires, cable ends, cable bundles and wire harness assemblies.

Lacquer
In cable manufacture to designate the liquid resin or compound applied to a fibrous braid to prevent fraying, wicking, moisture absorption, etc., in the braid.

Lacquer Finish
A finish applied over braided wire or cable for protection against fraying, wicking, moisture, absorption, abrasion, etc.

Ladder chain
a chain that comprises constitutional units always joined to each other through four atoms, two on each constitutional unit. (IUPAC)

Laminated Flat Cable
Flat cable consisting of insulated conductors lying parallel, adjacent conductors joined by a web. Application in electronics, telecommunications, computers, etc.

Laminated Tape
A tape consisting of two or more layers of different materials bonded together (i.e. aluminum/Mylar®) .

Lamination
1 ) The process of preparing a laminate. 2) any layer in a laminate. (Compare laminate and wood laminate.)

Lamp Cord
Flexible stranded paralleled 2-conductor cord, rubber or plastic insulated. Used for speaker cord, fans, lamps, etc., where not subject to hard usage.

LAN (Local Area Network)
A network spanning a limited geographical area, providing data communications between computers and peripherals and switching equipment.

LAND
The metal portion of a printed circuit board where the pads on a surface mount component are mated. Also called a footprint or a pad.

Lanemetre
Used particularly in connection with the transportation of trailers. One lanemetre is one metre of deck, with a width of 2.5 to 3.0 metres. The capacity of ships built for the transportation of new automobiles is normally expressed by the number of cars carried, or by the area of deckspace, in square metres.

Lang Lay Rope
Wire rope in which the wires in the strands in the rope are laid in the same direction

Lanyard
A device attached to certain connectors that permit uncoupling and separation of connector halves by a pull on a wire of cable.

Lanyard Release
A plug connector which may be separated from a counterpart receptacle by axial pull of an attached lanyard. (MIL-STD)

Lap Joint
A joint made by placing one adherend partly over another and bonding together the overlapped portions.

Lap Shear
Test to measure resistance to shear stress by bonding the ends of flat bars in an overlapping position.

Lapping film
Sheets of a thin plastic film with grit of varying coarseness (in microns) that are used to polish fiber endfaces.

Large core fiber
An optical fiber with a comparatively large core, usually a step-index type. There is no standard definition of “large,” but they are generally considered as fibers with diameters of 400 microns or more.

Laser (Fiber Optics)
Light Amplification by Stimulated Emission of Radiation, a device that generates intensified light, usually very directional and over a narrow range of wavelengths. Often a source of light in fiber optic systems.

Laser chirp
Noise created by reflected or crosstalk optical energy entering the lasing chamber.

Laser Diode
A semiconductor diode that emits light in a narrow spectrum; typically over 90% of the light output power concentrated within one angstrom.

Laser-optimized multimode fiber
The ISO/IEC 11801 standard defines two types: the OM3 50/125 fiber, with an effective modal bandwidth of 2,000 MHzkm at 850 nm, and the OM4 50/125 fiber, with 4,700 MHz-km bandwidth.

Lashing
Attaching a cable to a supporting strand or cable using a steel or dielectric filament around both cable and messenger.

Last mile
The last mile is the local access network that extends from the CO to the end-user subscriber. Also called the local loop network, it is traditionally copper-based and suffers from the bandwidth limitations of that media.

Latency
Delay of a signal in time, which can be caused by transmission, processing, rotation, and propagation delays.

Latent strain
A discoloration in a surface to which tape has been applied, which does not become noticeable until some time after removal, usually after the surface has been exposed to sunlight or heat.

Latex
A stable dispersion of polymeric substance in an essentially aqueous medium.

Latex caulks or sealants
A caulking compound or sealant using latex as the base raw material. The most common latex caulks are polyvinyl acetate and vinyl acrylic.

Launch Angle
Angle between the propagation direction of the incident light and the optical axis of an optical waveguide.

Launch cable
A known good fiber optic jumper cable attached to a source and calibrated for output power used used as a reference cable for loss testing. This cable must be made of fiber and connectors of a matching type to the cables to be tested.

Lay
The length measured along the axis of a wire or cable required for a single strand (in stranded wire) or conductor (in cable) to make one complete turn about the axis of the conductor or cable.

Lay Direction
The direction of the progressing spiral twist in a cable while looking along the axis of the cable away from the observer. The lay direction can be either “left” or “right”.

Lay Length
A term used in cable manufacturing to denote the distance of advance of one element (conductor) of a group of spirally twisted elements, in one turn measured axially.

Laydown
A step during the optical fiber manufacturing process in which gases are deposited as a wet “soot” upon a quartz rod by flame hydrolysis, ultimately creating a preform for the glass core and cladding of an optical fiber.

Layer
Consecutive turns of a coil lying in a single plane.

Lays
The twists in twisted-pair cable. Two single wires are twisted together to form a pair; by varying the length of the twists, or lays, the potential for signal interference between pairs is reduced.

LC Connector
A high density connector for fiber optic applications used in both public and private networks. This high performance connector is available in both singlemode and multimode.

Leaching and Non-Leaching
In a leaching wire the plasticizer will migrate when exposed to heat. A non-leaching wire will retain its plasticizer under extreme temperature conditions and remain flexible after baking.

Lead
A wire, with or without terminals, that connects two points in a circuit.

Lead Cured
A cable that is cured or vulcanized in a metallic lead mold.

Lead Dress
The placement or routing of wire and component leads in an electrical circuit.

Lead-in
The cable that provides the path for RF energy between the antenna and the receiver or transmitter.

Leakage
The undesirable passage of current over the surface of or through an insulator.

Leakage Current
The undesirable flow of current through or over the surface of an insulation.

Least square approximation (LSA)
A technique used by OTDRs to automatically measure splice attenuation.

LED
See LIGHT-EMITTING DIODE.

LED Node
Low-Entry Networking Node

Left Lay
1) Strand - Strand in which the cover wires are laid in a helix having a left-hand pitch; 2) Rope - Rope in which the strands are laid in a helix having a left-hand pitch

Legging
The drawing of filaments or strings when adhesive-bonded substrates are separated. (See also stringiness and webbing.)

Length
The distance of a communications link measured by a tester with a TDR. For TIA/EIA 568-B.2, the Permanent Link is limited to 90 meters of horizontal cabling embedded in the walls and ceiling plenum. Length is one of the ANSI/EIA/TIA-568-B.2 required tests for a Category 5e UTP cable limited to a total distance of 100 meters including the Permanent Link of 90 meters + 10 meters allowance of line cords, patch cords and up to two cross-connects in a link. (also see NOMINAL VELOCITY OF PROPAGATION)

Level
A measure of the difference between a quantity or value and an established reference.

Life Cycle
A test performed on a material or configuration to determine the length of time before failure in a controlled, usually accelerated environment.

Lifting
A situation where a section of tape has pulled away from the surface to which it has been applied.

Light
In the laser and optical communications fields, the portion of the electromagnetic spectrum that can be handled by the basic optical techniques used for the visible spectrum extending from the near ultraviolet region of approximately 0.3 micron, through t

Light (Fiber Optic)
An electromagnetic radiation in the wavelength range including infrared, visible, ultraviolet, and X rays, usually the range visible to the human eye, i.e., the energy that enables vision. Light travels in a vacuum at 300,000 km/sec. (186,281 miles per second).

Light Commercial Building
A building or portion thereof that is intended for use with one to four (1-4) non-residential exchange access lines per tenant.

Light Diffusion
Scattering of light by reflection or transmission. Diffuse reflection results when light strikes an irregular surface such as a frosted window or coated light bulb.

Light Emitting Diode
A semiconductor device that emits incoherent light from a p-n junction (when biased with an electrical current). Commonly called LED.

Light Intensity Ratio
Ratio of input light intensity to the output light intensity.

Light source
The fiber optic transmitter in an optical loss test set (OLTS) that uses one or more LEDs or lasers at specified wavelength.Lasers used in communication systems must be stabilized and operating in continuous wave or modulated at 2 kHz.

Light-emitting diode, LED
A semiconductor device that emits light when stimulated by an electrical current. Used in transmitters for multimode fiber links.

Light-Intensity Ratio
Ratio of input light intensity to the output light intensity.

Lightguide (Fiber Optic)
A fiber or a flexible bundle of fibers used to transmit light.

Lightpack Cable
A cable core design that allows bundles of optical fibers in a cable core without central strength members.

Lightwave Communications
Communications using light to carry the information.

Lightwaves
Electromagnetic waves in the region of optical frequencies. The term "light" was originally restricted to radiation visible to the human eye, with wavelengths between 400 and 700 nm. However, it has become customary to refer to radiation in the speed regi

Limiting Oxygen Index
Percentage of oxygen necessary to support combustion of a specified material.

Limits of Error
The maximum deviation (in degrees or percent) of a thermocouple or thermocouple extension wire from standard emf temperature to be measured.

Limpness
The ability of a cable to lay flat or conform to a surface as with microphone cables (also see Flexibility).

Line
The portion of a data circuit external to the data circuit-terminating equipment (DCE) that connects it to an exchange, other DCEs, or connects two exchanges.

Line Balance
The degree to which the conductors of a cable are alike in their electrical characteristics with respect to each other, to other conductors, and to ground .

Line Cord
A cord terminating in a plug at one end used to connect equipment or appliances to a power outlet.

Line Drop
A voltage loss occurring between any two points in a transmission line due to there sonance reactance or leakage of the line.

Line Impedance
Impedance as measured across the terminals of a transmission line; frequently the characteristic impedance of the line.

Line Level
Refers to the output voltage level of a piece of electronic equipment. Usually expressed in decibels (e.g., O dBv).

Line Loss
The total of the various energy losses occurring in a transmission line.

Line Speed
The maximum rate of data transfer for a given line.

Line Voltage
Voltage existing in a cable or circuit.

Linear
Polymers made up of one long continuous chain, without any excess

Linear chain
A chain with no branch points intermediate between the boundary units (i.e. the end-groups or other branch points). (IUPAC)

Linear copolymer
A copolymer, the macromolecules of which are linear chains.

Linear polymer
A polymer, the macromolecules of which are linear chains.

Linemap
A term referring to the termination pinout pairs of cable. (also see CONTINUITY and WIREMAP)

Link
An assembly of telecommunications facilities between two points, not including terminal equipment. The interconnection of two nodes in a network. A link may consist of a data communications circuit or a direct channel (cable) connection. It excludes equipment cables and work area cables. An optical cable with connectors attached to a transmitter and receiver.

Link Budget
Optical loss budget that determines the maximum distance allowable between station. Loss and dispersion factors are included.

Link, fiber optic
A combination of transmitter, receiver and fiber optic cable connecting them capable of transmitting data. May be analog or digital.

Linux
A contraction of  “Linus’ Unix”

Listed
Equipment included in a list published by an organization, acceptable to the authority having jurisdiction, that maintains periodic inspection of production of listed equipment, and whose listing states either that the equipment or material meets appropri

Lite
One piece of glazing (also spelled light), synonym: pane.

Litz wire
Wire made from a number of fine, separately-insulated strands specially braided or woven together for reduced skin effect and hence lower resistance to high frequency currents for lower RF losses. The name is Litzendraht wire, German for bundled wire.

Living copolymerization
A copolymerization which is a living polymerization. (IUPAC)

Living polymerization
A chain polymerization in which the concentration of kinetic-chain carriers, under the appropriate conditions for synthesis, remains constant for a period many times longer than the duration of the synthetic procedure. Often, the absence of chain transfer is implied in the term "living polymerization". (IUPAC)

Load
A device that consumes power from a source and uses that power to perform a function.

Load transfer device
Any device embedded in the concrete on both sides of a pavement joint to prevent relative vertical movement of slab edges.

Local access and transport area (LATA)
The geographic area that is the domain of the local exchange carrier. Bell operating companies are generally precluded from carrying traffic across LATA boundaries; this traffic must be handed off to an interexchange carrier.

Local Area Network (LAN)
A data communications network consisting of host computers or other equipment interconnected to terminal devices, such as personal computers, often via twisted-pair or coaxial cables. LAN's allow users to share information and computer resources. Typically, a network is limited to a single premises.  1)A baseband or broadband interactive bi-directional communication system for video or data use on a common cable medium.  2)A communications system whose dimensions typically are less than five kilometers. Transmissions within a local area network generally are digital, carrying data among units.

Local Exchange Carrier
The local wired phone company. The phone carrier providing local transmission services.Defined as either Independent or regional Bell operating company (RBOC).

Local injection and detection (LID)
A type of core alignment fusion splicer that injects light through a macrobend prior to the splice point and detects the light through a macrobend past the splice point. This allows the splicer to achieve maximum core-to-core alignment.

Local loop
The connection between a customer’s telephone or data equipment and a local exchange company or other telephone service provider.

Local Multipoint Distribution System (LMDS)
A “wireless cable” service operating in the 28-GHz band. LMDS uses low-power transmitters, configured in a cellular-like arrangement to transmit video to receivers in homes and businesses.

Locator
Device for positioning terminals, splices or contacts into crimping dies, positioner, or turret heads. See STOP PLATE. (MIL-STD)

Locking Spring
A device either on the contact or in the insert to retain the contact in an insert or body. (MIL-STD). Also called Contact Retainer

Locking Torque
Test designed to measure breakaway and prevailing torque of a threaded piece coated with thread locking adhesive.

Log Periodic Antenna
A broadband antenna where the electrical lengths and element spacings are chosen so the bi-directional radiation pattern, impedance and other antenna properties are repeated for several frequencies. The bandwidth is approximately the ratio of the longest dipole element to the shortest.

Long chain
A chain of high relative molecular mass. (IUPAC)

Long Wavelength
A commonly used term for light in the 1300 and 1550 nm ranges.

Long Wire Antenna
Any conductor length in excess of one-half of a wavelength. In a residential television installation, a horizontal run or unshielded lead-in will act as a long-wire antenna and introduce additional signal on top of the regular antenna signal causing ghosts, echoes, and pixelation.

Long-chain branch
A polymeric offshoot from a branched chain. (IUPAC)

Longitudinal Change (Shrink Tubing)
The change in length of tubing when recovered. Expressed in the percent change from the original length.

Longitudinal Conversion Loss
A ratio expressed in dB, of measured differential voltage relative to the common mode voltage on a conductor pair applied at the same end.

Longitudinal Conversion Transmission Loss
A ratio expressed in dB, of measured differential voltage relative to the common mode voltage on a conductor pair applied at the opposite end.

Longitudinal Shield
A tape shield, flat or corrugated, applied longitudinally with the axis of the core being shielded.

Longitudinal Shrinkage
A term generally applied to shrink products denoting the discrete axial length lost through heating in order to obtain the recovered diameter.

Longitudinal Wrap
Tape applied longitudinally with the axis of the core being covered.

Loop Antenna
An antenna consisting of one or more complete turns of a conductor; usually tuned to resonance by a variable capacitor connected to the terminals of the loop. It measures magnetic-field strengths at frequencies <30 kHz.

Loop Resistance
The total resistance of two conductors measured round trip from one end. Commonly used term in the thermocouple industry.

Loop tack
The initial attraction or grab of an adhesive to a substrate without any external pressure. Measured in pounds per lineal inch (PLI).

Loop Thru
A high impedance parallel connection. Also called Bridging

Loopback, or loop-back
The routing of electronic signals, digital data streams, or flows of items back to their source without intentional processing or modification. This is primarily a means of testing the transmission or transportation infrastructure. Example applications exist. It may be a communication channel with only one communication endpoint. Any message transmitted by such a channel is immediately and only received by that same channel. In telecommunications, loopback devices perform transmission tests of access lines from the serving switching center, which usually does not require the assistance of personnel at the served terminal. Loop around is a method of testing between stations that are not necessarily adjacent, where in two lines are used, with the test being done at one station and the two lines are interconnected at the distant station. A patch cable may also function as loopback, when applied manually or automatically, remotely or locally, facilitating a loop-back test. Where a system (such as a modem) involves round-trip analog-to-digital processing, a distinction is made between analog loopback, where the analog signal is looped back directly, and digital loopback, where the signal is processed in the digital domain before being re-converted to an analog signal and returned to the source.

Looping-in
Wiring method which avoids tee joints by carrying the conductor or cable to and from the point to be supplied.

Loose Buffer (Fiber Optic)
Also called "loose tube," a protective tube loosely surrounding a cabled fiber, often filled with a gel.

Loose Tube
Type of cable design in which coated fibers are encased in buffer tubes offering excellent fiber protection and segregation. Mainly used in outdoor cable types.

Loose tube cable
A type of cable where the internal 250-micron fibers are loose within buffer tubes. Types include stranded, central tube, OPGW, ADSS, and microduct cable. Also known as loose buffer cable.

Loose tube gel filled (LTGF)
A loose tube cable structure with buffer tubes filled with gel to restrict moisture intrusion. Mostly replaced with “dry” techniques, it is still used in areas of extreme low temperatures.

Loose-Tube
Type of cable design in which coated fibers are encased in buffer tubes offering excellent fiber protection and segregation. Mainly used in outdoor cable types.

Loosely-coupled mode
One example would be a high order mode from a LED coupled into a multimode fiber. Higher order modes limit the bandwidth of optical fibers.

Loss
1) Energy dissipated without performing useful work.  2) A decrease in power suffered by a signal as it is transmitted from one point to another (transmission loss).

Loss budget
The amount of power lost in the link. Often used in terms of the maximum amount of loss that can be tolerated by a given link.

Loss Factor
The product of the dissipation and dielectric constant of an insulating material. The loss factor of an insulating material is equal to the product of its dissipation and dielectric constant.

Loss windows
Fiber optic transmission typically occurs at 850, 1300, 1310, 1550, and/or 1625 nm. These “windows” were selected because absorption and scattering losses were lower within them. These wavelengths require light sources and photodetectors that operate efficiently over multimode and single-mode fibers. The newer term “bands” is used to define optical windows that match up with optical amplifiers and their optimum transmission wavelengths. The history of the usage comes from the availability of sources and detectors and their operating characteristics over an optical fiber due to the absorption effects at different wavelengths.

Loss, optical
The amount of optical power lost as light is transmitted through fiber, splices, couplers, etc.

Lossy
Having poor efficiency.

Lossy Line
A cable having large attenuation per unit of length.

Lot Number
The number that identifies one production run of material.

Low Frequency (LF)
A band of frequencies extending from 30 kHz to 300 kHz in the radio spectrum, designated by the Federal Communications Commission.

Low Loss
A cable that has relatively small power loss over long lengths.

Low Loss Dielectric
An insulating material that has a relatively low dielectric loss, such as polyethylene or Teflon.

Low Noise Cable
Cable configuration specially constructed to eliminate spurious electrical disturbances caused by capacitance changes or self-generated triboelectric noise.

Low Tension
Low voltage, as applied to ignition cable.

Low Voltage
Defined by the National Electrical Code as 600 Volts and less. AEIC, ICEA, and UL generally define cables rated up to 2KV as Low Voltage.

Low-smoke zero halogen (LSZH) cable
The standard cable used in Europe in place of plenum or risercable types. Internationally, LSZH cables are used in place of plenum and riser cable jackets. In North America, LSZH cables are used on ships and in tunnels. Also known as zero halogen cable.

Lug
Termination, usually crimped or soldered to the conductor, with provision for screwing on to the terminal. Sometimes referred to as Solder Lug.

mA. Milliampere
One-thousandth of an ampere (10-3).

Machine polishers
Automated polishers that are capable of polishing from two to 32 connectors at one time. These polishers can provide uniform low reflection polishes (e.g., PC, SPC, UPC, APC).

Macrobending
In an optical fiber, all macroscopic deviations of the axis from a straight line; distinguished from microbending.

Macrocycle
A cyclic macromolecule or a macromolecular cyclic portion of a molecule. (IUPAC)

Macromolecule
A large-sized molecule; another name for polymer. a molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetition of a number of constitutional units. (IUPAC)

Macromonomer
A monomer which is a polymer of an oligomer. (IUPAC)

Macromonomeric unit / macromer
The largest constitutional unit contributed by a single macromonomer molecule to the structure of a macromolecule. (IUPAC)

Magnet Wire
Insulated wire intended for use in windings on motor, transformer, and other coils for electromagnetic devices.

Magnetic Field
The region within which a body or current experiences magnetic forces.

Magnetic Flux
The rate of flow of magnetic energy across or through a surface (real or imaginary).

Magnetic Noise
Caused by current frequency. An AC powerline creates a magnetic field around that cable. This magnetic field causes the magnetic noise in neighboring control or instrumentation circuits.

Main chain / backbone
That chain to which all other chains (long or short or both) may be regarded as being pendant; where two or more chains could equally well be considered to be the main chain, that one is selected which leads to the simplest geometrical representation of the molecule. (IUPAC)

Main cross-connect (MC)
A cross connect for first and second level cabling, e.g., from equipment facility connecting to all other locations (ICs and HCs). Usually would consist of a distribution or patch panel.

Main distribution frame (MDF)
A wiring arrangement that connects the telephone lines coming from outside on one side and the internal lines on the other. A main distribution frame may also carry protective devices as well as function as a central testing point. The MDF has been changed to "MC" (main cross-connect) in ANSI/EIA/TIA-568-B.2. The MC is the point at which outside service lines interface to inside service and then to IC’s or to TC’s.

Mainframe
A large computer system.

Mainframe OTDR
An OTDR with a larger chassis than a mini OTDR. Mainframe OTDRs have CRT displays, internal printers and are larger and heavier than most OTDRs. They were the most common type up till the early 1990s. Mainframes could also be provided with different laser and fiber modules as needed.

Major Trading Area (MTA)
A personal-communications-service area designated by Rand McNally and adopted by the Federal Communications Commission to determine the 51 MTAs in the US.

Manchester Encoding
An encoding method which involves a digital state change (0 to 1 or vice versa) for every bit representation occurring in the middle of the transmitted bit. Useful in local area networks because it is self-clocking. The receiver can develop the data clock from the transmitted data stream. Used in Token Ring and Ethernet systems. Standard Ethernet uses Manchester encoding which results in 10 Mbps throughput at 10 MHz frequency (one-for-one).

Mandrel
A mechanical device of a specific diameter that strips out higher order modes from multimode fibers.

Manufactured Unit
A quantity of finished adhesive or finished adhesive component, processed at one time. (Compare batch.) Discussion—The manufactured unit may be a batch or a part thereof.

MAP
Multiple Application Platform, Linux powered chassis

MAP 1-step Reference Method
Unidirectional, Single MTJ. DUT end referenced to mORL detector. Used when two ILs are required, one for each end.

MAP 2-step Reference Method
Bi-Directional, Dual MTJ each referenced to mORL but not to each other. Used when MTJ cannot be mated to each other. Gives total IL.

MAP 3-step Reference Method
Uni or Bi-directional, dual MTJ, each referenced to mORL and to each other. Gives total IL.

Mapping
The act of associating logical representations with their physical counterparts.

Margin
The amount of additional loss that can be tolerated in a link.

Marine Eye
A style of hardware with a drilled eye and a drilled shank into which wire rope is inserted for swaging

Marker Tape
A tape laid parallel to the conductors under the jacket in a cable, imprinted with manufacturer's name and/or specification to which the cable is made.

Marker Thread
A colored thread laid parallel and adjacent to the strands of an insulated conductor which identifies the cable manufacturer. It may also denote a temperature rating or the specification to which the cable is made.

Marking
A printed identification number or symbol applied to the surface of tubing or cable jackets.

Marline Spike
Tapered steel pin used in splicing wire rope

MARS
Mulitcast Address Resolution Server

Mask
A peelable, water soluble, or solvent soluble compound that is used to prevent solder from filling in areas that need to be solder free. 

Master Antenna Television (MATV)
A combination of components providing multiple television receiver operations from one antenna or group of antennas normally on a single building.

Mastic
Meltable coating used on the inside of some shrink products which, when heated, flows to encapsulate the interstitial air voids.

Mastic adhesive
A gap-filling adhesive applied as a paste or putty-like material.

Matched-clad optical fiber
Optical fiber with a cladding of consistent refractive index up to the core boundary, resulting in the desired single-mode step-index profile. Used where fibers of different periods are spliced together as they produce lower attenuation readings and are less susceptible to bending losses.

Mate
The joining of two connectors. (MIL-STD)

Material
a substance useful for structural purposes.

Material dispersion
Dispersion caused by differential delay of various wavelengths of light in a waveguide material.

Material safety data sheet (MSDS)
Technical bulletin required by OSHA detailing information about the physical or health hazards of a chemical or mixture.

Material Scattering Loss
Loss due to fluctuations in the refractive index and to inhomogeneities in material composition and temperature.

Mating connector
A connector on the test fixturing that connects, or mates, to a connector on the device-under-test.

Mating Face
1) Shared boundary defined by common physical interconnection characteristics (often including a connector), signal characteristics and meanings of interchanged signals.  2) A device or equipment making inter-operation of two systems possible; for example, a hardware component or common storage register.  3) The two surfaces on the contact side of a mating connector or plug-in component (e.g. relay) and receptacle, which face each other when mated. (MIL-STD)Also called Interface.

Mating Face Seal
A seal which prevents the passage of moisture or gases into or out of the connecting interface of two connectors in mated condition.

Matrix
The part of an adhesive which surrounds or engulfs embedded filler or reinforcing particles and filaments.

Maturing temperature
The temperature, as a function of time and bonding condition, that produces desired characteristics in bonded components. Discussion—The term is specific for ceramic adhesives.

MaxCell
A type of flexible fabric inner duct used to increase capacity of ducts.

Mean time between failure (MTBF)
Developed by the military to estimate maintenance or replacement times for various pieces of high-end equipment, MTBF is based upon statistical evidence derived from in use testing under extreme conditions (simulated or actual environment). Testing is performed by the manufacturer of the equipment or an independent test facility.

Mechanical adhesion
See mechanical adhesion under adhesion.

Mechanical splice
A fiber splice accomplished by fixtures or materials, rather than by thermal fusion. Index matching material may be applied between the two fiber ends. A semi-permanent connection between two fibers, made with an alignment device and refractive index matching fluid or adhesive.

Mechanism
The step-by-step changes by which a chemical reaction occurs

MEDIA (Telecommunications)
Wire, cable or conductors used for telecommunications.

Media outlet
A small patch panel located at work areas allowing quick termination of voice, video, and data connectors.

Media, Telecommunications
Wire, cable, or conductors used for telecommunications.

Medium
Material used for the transmission of signals.

Medium Voltage
2001 Volts to 35KV.

Medium-density polyethylene (MDPE)
A flexible, environmentally-stable thermoplastic used in outside cable jacketing.

Mega (M)
One million, or 1,000,000

Megabit (Mb)
One million bits.

Megahertz (MHz)
One million cycles per second.

Megarad
A unit for measuring radiation dosage. 1 megarad = one million rads = 106 rad or 106 cJ/kg.

Megohmmeter
An instrument used to measure insulation resistance (Readings are in megohmes).

Melt Extrude
To heat a material above its crystalline melt point and extrude it through an orifice.

Melting Point
The temperature at which crystallinity disappears when crystalline material is heated.

Member
A group of insulated wires to be cabled with other stranded groups into multiple-membered cable.

Membrane Press
A hot press design which permits laminates or veneer to be glued to a surface that is not flat, by using a rubber membrane that is inflated with a hot fluid.

Membrane pressing
A process in which an adherend is brought in intimate contact with a substrate to form an assembly by application of overpressure to a flexible film.

MEMS
Micro-Electromechanical Sytems

Mercaptan
An organic compound containing –SH groups; a main curing agent for polysulfide adhesives and sealants.

Message switching
Enables a single communications channel to be used simultaneously for more than one node.

Messenger
The linear supporting member, usually a high strength steel wire, used as the supporting element of a suspended aerial cable. The messenger may be an integral part of the cable, or on the exterior.

Messenger Strand
Galvanized strand or bronze strand used to support telephone and electric cables

Messenger wire
Galvanized wire ranging from 1/4” to 9/16” which is placed between poles and which standard cable types are lashed.

Metal foil
Thin, flexible sheets of metal (e.g. aluminum and lead) used as tape backings because of inherent properties such as weather-resistance, reflectivity, etc.

Metal To Metal Bottoming
In cylindrical connectors, the situation in which the shell surface of the receptacle bottoms (contacts) the inside rear portion of the mating plug.

Meter (m)
One meter equals 3.281 feet.

Method of Moments
Equations for numerically computing electromagnetic fields.

Metric Cable
Cable designed and manufactured to metric sizes and tolerances

Metropolitan area network (MAN)
An interconnected data transmission system connecting users and LANs in a localized geographical area such as a city.

Metropolitan Statistical Area (MSA)
An MSA denotes one of the 306 largest urban population markets as defined by Rand McNally and designated by the Federal Communications Commission as a guide to determine coverage areas for cellular networks. Two cellular operators are licensed in each MSA.

MFC Library
Microsoft Foundation Class Library

MHO
An electrical unit of conductivity, being the conductivity of a body with the resistance of one ohm.

MHV (Miniature High Voltage)
Coaxial connector with bayonet coupling mechanism. Working voltage 2.2 kV DC.

MHz
One million cycles per second = megahertz = 106 Hz.

Micro (µ)
One millionth

Micro Farad
One millionth of a farad. This is the common unit for designating capacitance in electronics and communications.

Microbending
Curvatures of the fiber which involve axial displacements a few micrometers and spatial wavelengths of a few millimeters. Microbends cause loss of light and consequently increase the attenuation of the fiber. An effect where small stresses or flaws create attenuation. Mostly an extrinsic effect caused by tie wraps and point deformations onto the fiber that allow light to escape. Intrinsic sources are flaws or defects in the core/cladding boundary created during the manufacturing process.

Microbending Loss
Loss due to small geometrical irregularities along the core-clad interface of the fiber.

Microcell
A small cell site in a personal-communications-services network. Personal-communications-services networks use many microcells.

Microduct
Small HDPE ducts up to 16 mm in diameter that can be installed in empty or partially filled ducts to provide space for microduct fiber optic cables.

Microduct cable
Microduct cables are designed for high-density fiber counts in a small optical cable, normally between 5-16 mm. Designed for blowing into microducts.

Microfarad (MF)
One-millionth of a farad (uf, ufd, mf and mfd are common abbreviations).

Micrometer (µm)
One millionth of a meter or a micron. Conventional unit of measurement for optical fibers.

Micromicrofarad
One-millionth of a microfarad (uuf, uufd, mmf, mmfd mm F are common abbreviations).

Micron (um)
Millionth of a meter = 10-6 meter.

Microphonics
Noise in a system caused by mechanical vibration of components within the system.

Microscope, fiber optic inspection
A microscope used to inspect the end surface of a connector for flaws or contamination or a fiber for cleave quality.

Microstrip
A type of transmission line configuration which consists of a conductor over a parallel ground plane and separated by a dielectric.

Microwave
A short (usually less than 30 cm.) electrical wave. RF signals between 890-MHz and 20-GHz. Point-to-point microwave transmission is commonly used as a substitute for copper or fiber cable.

Microwave Frequency
The frequency of a microwave, usually above 1 gigahertz.

Mid-entry
Opening a cable in the middle of a span to access the fibers. Also known as an express entry.

Midget
Referring to an inlet or outlet with a shallow depth. Commonly mounted in areas where space is limited.

MIDP
Mobile Information Device Profile

Migration
The movement of some metals, notably silver, from one location to another.

MII Format
A video recording format used by broadcasters.

MIL
1) Military specification for wire; 2) 0.001" (1/1000 inch) one 1000th of an inch; 3) A unit used in measuring diameter of wire or thickness of an insulation over a conductor.

MIL-DTL-17
DSCC specification for Radio Frequency cables, flexible and semi-rigid.

MIL-SPEC
United States Defense Standard, often called a military standard, "MIL-STD", or "MIL-SPEC". A MIL-SPEC for quality standards for electronic parts is MIL-STD-202. 

Military Specification
A specification governing the manufacture of specialty wire ropes and aircraft cables required in various military and non-military applications. See Cable Specifications

Military tactical cable
Heavy-duty cable designed for rugged installations and operations.

Milli
One-thousandth

Millimeter (mm)
One millimeter equals 0.03937 inches.

minEMBc
An abbreviation for minimum calculated effective modal bandwidth, minEMBc is used to calculate the bandwidth of multimode fiber at Gigabit data rates.

Mineral Insulated
Cable and thermocouple wire consisting of one or more conductors surrounded by magnesium oxide insulation and enclosed in a liquid- and gas-tight metallic sheathing.

Mini OTDR
Mini OTDRs emerged in the 1990s as a low-cost, lightweight version of the mainframe OTDR. Features include AC/DC power, LCD display, and various modules for specific fiber types and corresponding wavelengths. Usually without a printer, they can store traces on disk, memory card, or their internal hard disk.

Mini Zipcord
A separable two-fiber breakout style cable.

Miniature Wire
Insulated conductors of approximately 20-34 AWG.

MiniBNC connector
A keyed connector with a 2.5-mm ferrule and bayonet coupling mechanism. It was the predecessor to the ST connector.

Minimum Bending Radius
Ratio of the diameter of the pulley used in an application (D) to the diameter of the wire rope (d)

Minimum Dynamic Bending Radius
The minimum permissible radius for flexible applications of the cable.

Minimum Static Bending Radius
The minimum permissible radium for fixed installation of the cable. This radium is used I climatic tests.

Mining Cable
A flame retardant cable especially constructed to withstand long time immersion or exposure to moisture for underground use in the environment of a mine or tunnel.

Mismatch
A termination having a different impedance from that for which a circuit or cable is designed.

Mismatch (Connector Impedance or Line Impedance)
1) The condition in which the impedance of a source does not match or equal the impedance of the connected load. This reduces power transfer by causing reflection.  2) A termination having a different impedance than that for which a circuit or cable is designed.

Miswire
An unintended connection which is the result of a misplaced contact within a connector.

Mobile Telephone Switching Office (MTSO)
The central computer that connects a cellular-phone call to the public telephone network. The MTSO controls the entire system’s operations, including monitoring calls, billing, and handoffs.

Modal Dispersion
Pulse spreading due to multiple light rays traveling different distances and speeds through an optical fiber.

Mode
A light path. One of the components of a general configuration of a propagating wave front.

Mode (Fiber Optic)
One of the components of a general configuration of a propagating wave front. Mode is characterized by a particular geometrical pattern and propagation constant.

Mode conditioning patchcord (MCPC)
Designed for GbE and Fibre Channel links using legacy multimode fibers and VCSEL light sources operating at 850 nm. Normally it is a pair of duplex jumpers that are installed between the transmission equipment at each end of the fiber link. The transmit side has a short single-mode section “offset” fusion spliced to MMF so the light is coupled outside of the center core defect of the MMF. The receiver portion is entirely multimode.

Mode coupling
In an optical fiber, the exchange of power among modes. The exchange of power may reach statistical equilibrium length.

Mode field diameter
A measure of the core size in singlemode fiber.

Mode Field Diameter (MFD)
The diameter of optical energy in a singlemode fiber. Because the MFD is greater than the core diameter, MFD replaces core diameter as a practical parameter.

Mode filter
A device that removes optical power in higher order modes in fiber.

Mode power distribution (MPD)
The relative mode power in each mode groups of a multimode fiber.

Mode scrambler
A device that mixes optical power in fiber to achieve equal power distribution in all modes. Mode stripper: A device that removes light in the cladding of an optical fiber.

Modem
Device which places and receives data signals over a common carrier's communication facility.

Modifier
Any chemically inert ingredient added to an adhesive formulation that changes its properties.

Modular Jack
This term is outmoded, see Outlet/Connector, Telecommunications.

Modular Plug
A series of connectors designed for ease of use and flexibility. They are characterized by locking plastic tabs on the bottom and typically appear in three configurations: RJ-11 (4-conductor), RJ-12 (6-conductor) and RJ-45 (8-conductor).

Modulated laser
A laser module that allows users to control output power by varying a control voltage, which turns the laser on and off.

Modulation
In fiber optics, the manner in which information is coded into light for transmission through a fiber.

Modulator
A waveguide device used externally to the laser to electrooptically change the refractive index of the waveguide in response to an applied electric field. The phase changes induced can result in amplitude modulation of light at the output port.

Modulus of Elasticity
The ratio of stress to strain in an elastic material.

Modulus, secant
Slope of the line connecting the origin and a given point of the stress-strain curve.

Modulus, tangent
Slope of the line touching (tangent to) the stress-strain curve at a given point on the curve.

Moisture Absorption
The amount of moisture , in percentage, that a material will absorb under specified conditions.

Moisture Content
Percent moisture content is equal to the weight of water divided by the weight of bone-dry wood x 100.

Moisture Meter
A small electronic device designed to determine the moisture content of wood stock.

Moisture Resistance
The ability of a material to resist absorbing moisture from the air or when immersed in water.

Mold, Potting, Electrical, Connector
An item, solid or split, designed to be used as a hollow form into which potting compound is injected and allowed to cure or set to seal the back of an electrical connector. The potting may eliminate the need for a backshell on the connector. The form may or may not be removable after potting.

Molded Plug
A connector molded on either end of a cord or cable.

Mono Filament
A single-strand filament as opposed to a braided or twisted filament.

Monochromatic
Consisting of a single wavelength. In practice, radiation is never perfectly monochromatic but, at best, displays a narrow band of wavelengths.

Monochrome Signal
A television signal that does not contain any color information, a "black and white" signal.

Monomer
The basic chemical unit used in building a polymer.

Monomeric unit / mer
The largest constitutional unit contributed by a single monomer molecule to the structure of a macromolecule or oligomer molecule. (IUPAC)

Monomode
See single-mode.

Mooring Lines
Galvanized wire rope, usually 6x12, 6x24 or spring lay construction, for holding ships to dock

mORL Detector
2 mm detector for measuring Insertion loss.

mORL Module
The main “Engine” in any PCT setup, contains sources and detector

Motherboard
A printed circuit board used for interconnecting arrays of plug-in electronic modules or sub-assemblies.

Motor Lead Wire
Wire which connects to the usually fragile and easily damaged magnet wire found in coils, transformers, and stator or field windings. General requirements are abrasion resistance, toughness, flexibility, dielectric strength, thermal resistance and low pe

Moving Pictures Experts Group (MPEG)
Various standards, established by the, that define the amount of compression, and thereby the quality, of the resultant video information file.

MTJ
Master Test Jumper, launch and receive test cables, high quality Jumpers used to connect between the MAP/PCT instrument and the DUT.

MTP (MPO)
Multi-channel (4 to 72) connector from USConec (MPO is generic version).

Mucilage
An adhesive prepared from a gum and water. Also in a more general sense, a liquid adhesive which has a low order of bonding strength.

Mullion
External structural member in a curtain wall building, usually vertical. May be placed between two opaque panels, between two window frames, or between a panel and a window frame.

Multi
1000 volts 1000 volts

Multi-Conductor Cable
A cable consisting of two or more conductors, either cabled or laid in a flat parallel construction, with or without a common overall covering.

Multi-strand chain
A chain that comprises units always joined to each other through more than four atoms, more than two on each constitutional unit. (IUPAC)

Multicast
A single packet of information sent to a specific subset of network addresses.

Multiconductor
More than one conductor within a single cable complex.

Multifiber cable
An optical cable having more than one fiber.

Multifiber push-on connector (MPO)
A high-density connector that can terminate up to 24 singlemode or 72 multimode fibers in a single termination.

Multilongitudinal mode (MLM) laser
A laser, usually Fabry-Perot, that has a measured spectral width specified by the maximum root mean square of the spectral distribution (side modes), limited to no more than 20 dB down from the peak mode.

Multimedia
A means of conveying information with components in different media such as voice, music, text, graphics, image and video.

Multimedia Cable
A single communication cable used for the transmission of audio, data and video signals.

Multimeter
An instrument used to measure resistance, current and voltage. 

Multimode
Many light rays (modes) propagating through the fiber core.

Multimode Fiber
An optical waveguide in which light travels in several modes. Typical core and cladding sizes are 62.5 and 125 µm, respectively.

Multimode Optical Fiber
An optical fiber that will allow many bound modes to propagate. The fiber may be either a graded-index or step-index fiber. See also: Optical Fiber Cable.

Multimode Propaganda
A method of introducing a light pulse with multiple light rays (modes) into an optical fiber. Multimode is typically used for short-haul applications of less than 2 KM using relatively inexpensive light sources usually operating at a 850 or 1300 nanometer wavelength. Gigabit Ethernet uses an 850 VCSEL laser while most other applications use Light Emitting Diode (LED) light sources.

Multimode-Fiber
A type of optical fiber that supports more than one propagation mode.

Multiple Conductor Cable
A combination of two or more conductors cabled together and insulated from one another and from sheath or armor where used.

Multiple Conductor Concentric Cable
An insulated central conductor with one or more tubular stranded conductors laid over it concentrically and insulated from one another.

Multiple system operator (MSO)
A cable television provider.

Multiple-Conductor Cable
A combination of two or more conductors cabled together and insulated from one another and from sheath or armor where used.

Multiple-layer adhesive
Film adhesive, usually supported, with a different adhesive composition on each side.

Multiplex
Combining two or more signals into a single bit stream that can be individually recovered.

Multiplexer (Mux)
A device which combines two or more separate signals for transmission through a single fiber. Optical multiplexer combines signals at different wavelengths. Electronic multiplexer combines TDM or FDM signals electronically before they are converted into optical form.

Multiplexing
Simultaneous transmission of two or more messages over the same cable pair.

Multiprocessing
The ability of a system to run two or more processors simultaneously.

Multiprotocol label switching (MPLS)
An overall data-carrying protocol that encompasses circuit based and packet-switching services such as ATM, SONET, and Ethernet, as well as network digital formats such as VoIP and IPTV.

Multitenant data center (MTDC)
A facility that provides Internet infrastructure services, such as electrical power, fire suppression, security, cooling, and network access, usually over optical fiber. Some firms lease datacenter space to other providers or individual enterprises. Colocation data centers sell space on the basis of racks, cabinets, or cages.

Multiuser telecommunications outlet assembly (MUTOA)
Used in work areas of premises networks to allow multiple terminations.

Mutual Capacitance (Cm)
1) Capacitance between two conductors when all other conductors are connected together to shield and ground.  2) Capacitance between two conductors when all other conductors including ground are connected together and then regarded as an ignored ground.

Mutual Inductance
The ratio of voltage induced in one conductor to the time rate of current change in the separate conductor causing this induction.

MUX
A short form slang of multiplex. Also MUXED, MUXING.

mV (Millivolt)
One thousandth of a volt.

mW (Milliwatt)
One thousandth of a watt.

Mylar®
DuPont trademark for polyethylene terephtalate (polyester) film.

N (Neill)
Coaxial connector with screw type coupling mechanism. Available in 50 ohm and 75 ohm version. Frequency range DC - 18 GHz (50 ohm) and DC-1 GHz (75 ohm), respectively.

N/mm2
Newtons per squared mm. Typical measurement for Tensile Strength.

Nano
One-billionth

Nanometer (nm)
One billionth of a meter (nm).

Nanosecond (ns)
One billionth of a second (10-9 seconds).

Narrowband
Mobile or portable radio services, usually paging and data services.

National Electrical Code® (NEC)
A U.S. consensus standard published by the National Fire Protection Association (NFPA) and incorporated in OSHA regulations. (The Canadian Counterpart is the CE Code.)

National Electrical Code® Article 725
The NEC Article which covers remote control signal and communication power limited circuits that are not an integral part of the device or appliance.

National Electrical Code® Article 760
The NEC Article which covers the fire and burglar alarms installation of wire and equipment operating at 600 Volts or less.

National Electrical Code® Article 800
The NEC Article which covers telephone, telegraph as well as outside wiring for fireand burglar alarms.

National Electrical Safety Code (NESC)
This outside plant code contains basic safety provisions that cover supply, communication lines, equipment, and work practices of personnel employed by utilities.

National Institute of Standards and Technology (NIST)
A U.S. government organization that develops standards in support of industry, commerce, scientific institutions, and all branches of government. The calibration of test equipment is traceable to NIST equipment.

National Telecommunications and Information Administration (NTIA)
An agency of the US Commerce Department, it is the President’s adviser on communications policy and is responsible for administering all federal government use of the radio spectrum, including military communications.

National Television Standards Committee (NTSC)
Committee that defines specifications and methods for displaying video information on a standard television.

Near End Crosstalk (NEXT)
Refers to the undesired coupling of signals from the transmit pair onto the receive pair on the same (=near) end. NEXT isolation is expressed in dB and is a measure of how well the pairs in a cable are isolated from each other.

Near Infrared
The part of the infrared electromagnetic spectrum near visible wavelengths, in the range of 700 to 1500/2000 nm.

NEAR-END CROSSTALK (NEXT)
The coupling of power from the transmitted signal pair to an adjacent pair at the same transmitting end of the LAN cable.

NEC Type CL2
A Class 2 power-limited type cable for general use applications within a building under NEC Article 725, this type design is "Listed" by UL. These cables meet a 70,000 BTU flame test.

NEC Type CL2P
A Class 2 power-limited cable which is suitable for use in plenums in accordance with NEC Article 725. The cable meets the requirements of UL 910 the Steiner Tunnel test which classifies fire and smoke characteristics. The cable is "Listed" by UL.

NEC Type CL2R
A Class 2 power-limited cable which is suitable for use in riser shafts in accordance with NEC Article 725. These cables meet the UL 1666 flame test and are "Listed" by UL.

NEC Type CL2X
A Class 2 power-limited cable which is suitable for restricted applications (Iess than 0.25" in diameter in residences, exposed lengths less than 10f t.) or else in raceways under NEC Article 725. These cables meet a VW-1 flame test and a re Listed by UL.

NEC Type CM
A general application communications cable, Listed by UL, for use within buildings under NEC Article 800. It meets the requirements of the 70,000 BTU flame test.

NEC Type FPL
A general application fire p rotection cable for use within buildings in accordance with NEC Article 760. These cables are Listed by UL and meet the 70,000 BTU flame test.

NEC Type MP
A general use, multipurpose cable which may be employed interchangeably in either a communications (Article 800), power-limited (Article 725) or fire protective (Article 760) application.

Neck down
The change in the cross section areas of a sealant as it is extended.

Neck splice
Necking or narrowing produces a high loss splice. Also caused by bad cleaves which leave a void between the fiber ends resulting in a narrow section during fusion.

Neoprene
A synthetic rubber with good resistance to oil, chemicals and flame. Also called polychloroprene.

Neper
An electrical unit similar to decibel, used to express the ratio between two amount of power existing at two distinct points. 1 Neper = 8.686 decibels.

Nest
The portion of a crimping die which supports the barrel during crimping. See Anvil. (MIL-STD)

net
One of the top-level Internet domain names

Net Tonnage (NT)
#ERROR!

NETBIOS
Network Basic Input/Output System.

NETVIEW
A network management offering from IBM.

NETWARE
A popular network operating system from Novell Inc.

Network
1) Series of points connected by communications channels; 2) Network of telephone lines normally used for dialed telephone calls; 3) Network of communications channels connected to the use of one customer. For purposes of data communications applications

Network access point (NAP)
A major Internet connection point that allows organizations to interconnect and exchange information and traffic to flow from freely from ISP to ISP.

Network adapter
A device such as an Ethernet card that enables a computer to be attached to a network.

NETWORK ADDRESS
A number giving a specific identification to a network attached device.

Network Architecture
Network topology and design.

Network Communications Cable (NCC)
Network Communications Cable, often called NCC, is generally used in the Riser Backbone Subsystem in locations not involving plenums. The cable consists of 24-AWG, annealed-copper conductors insulted with color-coded polyvinyl chloride (PVC) in twisted pairs, encased in an outer PVC jacket whose frictional properties permit it to be pulled in conduit without the aid of lubricants. This type of cabling used to be referred to as Direct Inside Wire (DIW).

Network equipment building system (NEBS)
A requirement for central office equipment in the North American Public Switched Telephone Network. Originally developed by Bell Labs (now Telcordia) in the 1970s and released as a public document in 1985.

Network Interface
The point of interconnection between building communications wiring and outside communications lines (telephone company facilities).

Network Interface Cards (NICs)
The piece of equipment that is installed into the expansion port of a personal computer and allows communication between the PC and the network.

Network Layer
The network layer is layer 3 of the OSI model. This layer sets up an end-to-end connection across a network determining which permutation of individual links to be used. Thus the network layer performs overall routing functions.

Network Operating System
NOS. The software component of a network. The NOS contains all instructions pertinent to data transfer, file manipulation and services and interfacing routines.

Network Operations Center (NOC)
The group responsible for the day-to-day care and feeding of a network. Also called a network control center (NCC).

Network Topology
The physical layout and interconnection of a network.

New Bedford, MA
City in Massachusetts in North America that is home to Fiber Optic Center's headquarters. New Bedford was known in the 19th Century as “the city that lit the world”, because as the active seaport which was home to the worldwide whaling industry, its products were used to light the lamps and later lighthouses throughout the U.S. and elsewhere. Whaleships were at sea for 3 or more years at a time in every direction, including both poles and everywhere in between. On returning back to the home port, goods gathered overseas were shared with others, as were stories of people, customs and cultures. Immigrants came from far places to man the ships, and many stayed and settled when their sailing days ended.

Newtonian Behavior
The property of a liquid in which its viscosity is constant over a stated range of strain rates.

Nick
A cut or notch in conductor strands or insulation. (MIL-STD)

Nip Roll
A pressure system designed to apply a large amount of pressure for an instant. This system is frequently used for hot melt, fast-set adhesives, or contact cements.

NODE
A connection point into a network. The node may perform several functions (i.e., file server, workstation, print server, bridge, etc.).

Noise
In a cable or circuit, any extraneous signal which tends to interfere with the signal normally present in or passing through the system.

Nomex®
DuPont's trademark for a temperature resistant, flame-retardant nylon.

Nominal
A descriptor applied to a dimension representing the center of the range of tolerance or a value if no tolerance is applied.

Nominal stress
The stress at a point calculated on the net cross section by simple elastic theory without taking into account the effect on the stress produced by discontinuities such as holes, grooves, fillets, or any combination of them.

Nominal Velocity of Propagation
"NVP" is the relative speed a signal travels on a conductor that is proportionate to the speed of light in a vacuum. Length measurements are determined by sending a signal down a line and measuring the reflected signal that comes back and factoring in the amount of time that it took to make the return trip. (also see c and LENGTH)

Non Hygroscopic
A material incapable of taking up or absorbing moisture from the air.

Non-Contaminating
Type of PVC jacket material whose plasticizer will not migrate into the dielectric of a coaxial cable and thus avoids contaminating and destroying the dielectric.

Non-draining
An adjective describing a chain macromolecule that behaves in a hydrodynamic field as though the solvent within the domain of the macromolecule were virtually immobilized with respect to the macromolecule. (IUPAC)

Non-Newtonian behavior
The property of a liquid in which its viscosity is not constant over a stated range of strain rates.

Non-Normal Jack
A chassis mounted device that provides a connection between a rear mounted receptacle and a front mounted receptacle.

Non-porous substrate
Substrate that is not permeable by air, water, etc.

Non-Rotating Wire Ropes
18x7 wire rope consisting of a 6x7 left lay Lang lay inner rope covered by twelve 7-wire strands right lay regular lay - also 19x7’s

Non-Wireline Cellular Company
The Federal Communications Commission licensed two cellular systems in each market—one for the local telephone company and the second, the “A” carrier, for other applicants. The distinction between A and B (the wireline cellular carrier) was meaningful only during the Federal Communications Commission’s licensing process. Once a system is constructed, it can be sold to anyone. Thus, in some markets today, the A and B systems are owned by telephone companies. One happens to be the local phone company for the area and the other is a phone company that decided to buy a cellular system outside its home territory.

Non-woven materials
Paper "tissues" or synthetic (e.g. rayon) non-woven fabrics.

Nonflammable
Incapable of being easily ignited or burned.

Nonvolatile content
The portion of a material that remains after volatile matter has been evaporated under specified ambient or accelerated conditions.

Nonzero dispersion-shifted fiber (NZDS)
Single-mode fiber designed for DWDM and optical amplifier applications. Specified in the ITU-T G.655 standard.

Norid Mobile Telecommunication System (NMT)
A European analog cellular standard operating at 450 and 900-MHz

Normal Jack
The same as a Non-Normal Jack, except that there is also an interruptible connection between the two rear mounted receptacles.

Normal Plug
A dual male connector that can be inserted into two vertical jacks to provide a continuous connection. Sometimes called a "looping" plug.

Notch
A cut or notch in conductor strands or insulation. (MIL-STD)

Novolak
A phenolic resin containing less than a 1:1 ratio of formaldehyde to phenol so that normally it remains thermoplastic until heated with an appropriate amount of a compound (for example, formaldehyde or hexamethylenetetramine) capable of giving additional linkages, thereby producing an infusible material.

Numerical Aperture (NA)
Measure of the range of angles of incident light transmitted through a fiber. Depends on the differences in index of refraction between the core and the cladding. (The number that expresses the light gathering ability of a fiber.)

Nylon
A group of polyamide polymers, used for wire and cable jackets with good chemical and abrasion resistance.

O Crimp
An insulation support crimp for open barrel terminals with a crimped form resembling an O. It conforms to the shape of round wire insulation.

O Ring
A doughnut-shaped ring of rubber used as a seal around the periphery of the mating insulator interface of cylindrical connectors.

O-Ring
An elastomer gasket enabling a moisture seal, having a circular cross section. See Rubber.

Occupational Safety and Health Administration (OSHA)
The main government agency for enforcement of safety and health law in the United States.

OCTOPUS
A cable adapter that transforms a 25-pair feeder into individual modular plugs.

ODC Connectors
ODC connectors are designed for the fiber to the antenna (FTTA) applications and can withstand harsh environmental conditions when being used outdoors. They are used for data and telecommunications in mobile radio, process, utility and traffic automation. They are also well suited for industrial, aerospace and defense, oil, wind power, rail transport and heavy machinery of digital information transmission applications. The ODC cable assembly is based on the N Type RF Coax connector and have passed tests like salt mist, vibration and shock and meet protection class IP68.

Off Center
Conductor displaced within the cross-section of its insulation, no longer concentric.

Off-core
Condition in which ayers of tape are in correct alignment, but tape is displaced sideways on core.

Offgassing
Percentage of a specified gas released during the combustion of insulation or jacketing material.

offsetting
Condition occurs when a printed tape is unwound and some of the printing ink is picked off by the adhesive or migrates into the adhesive. It is in effect a delamination of the ink.

Ohm (W)
Unit of electrical resistance. Resistance of a circuit in which a potential difference of one volt produces a current of one ampere.

Ohm-pound/mile
A unit of weight resistivity expressing the resistance of a wire one pound in weight and one mile in length.

Ohm’s Law
Stated E = IR, I = E/R, or R = E/I, the current I in a circuit is directly proportional to the voltage E, and inversely proportional to the resistance R.

Oil Aging
Cable aged in an accelerated manner by placement in an oil bath and heated to a p re-set temperature for a stated time.

Oil-Filled Cable
A self-contained pressure cable in which the pressure medium is low viscosity oil having access to the insulation.

Oligome
A low molecular weight polymer in which the number of repeating units is approximately between two and ten.

Oligomer
A substance composed of oligomer molecules. (IUPAC)

Oligomer molecule
A molecule of intermediate relative molecular mass, the structure of which essentially comprises a small plurality of constitutional units. (IUPAC)

Oligomerization
The process of converting a monomer or a mixture of monomers into an oligomer. (IUPAC)

Ooutlet Cable
A cable placed in a residential unit extending directly between the telecommunications outlet/connector and the distribution device.

Opaque
Not permitting the passage of light.

Open
The intended electrical path contains a gap, across which, electric current cannot pass.

Open Assembly Time
Period of assembly time when the adhesive film is exposed to the air.

Open Cell
Foamed or cellular material with cells which are generally interconnected.

Open Circuit
An incomplete circuit. A cable connected at one end only is an example of an open circuit. The opposite of a short circuit.

Open Entry Contact
A female-opening contact unprotected from possible damage or distortion from a test probe or other wedging device.

Open Office
A floor space division provided by furniture, moveable partitions or other means instead of by building walls.

Open system interconnection (OSI)
A seven-layered framework of standards for network communication. OSI creates an open systems networking environment where different systems can share data regardless of vendor or platform.

Open Time
Time during which the adhesive remains active without curing after being applied to the substrate. Alternate term for Assembly Time – The time period from the application ot the adhesive until the final application of pressure.

Operating Frequency
The maximum frequency at which a connector will function and yield satisfactory electrical performance.

Operating System
A software program or collection of programs that manage the computer’s hardware and provide an interface to that hardware for the end-user.

Operating Temperature
The maximum internal temperature resistant capabilities of a connector in continuous operation. (MIL-STD)

Operating Voltage
The maximum voltage at which a connector is rated to operate.

Operational support system (OSS)
Software that furnishes tools to provide network control, monitoring and business functions.

Operations, administration and maintenance (OAM)
A group of network management functions that provide fault indications, performance information, and network diagnosis.

Optical access networking (OAN)
An access network made up of optical transmission links as opposed to copper links composed of twisted-pair or coaxial cabling.

Optical add/drop multiplexer (OADM)
A multiplexer typically used in DWDM systems to allow a wavelength to be added or dropped optically. Can be fixed (FOADM), reconfigurable (ROADM), or dynamic (DOADM).

Optical amplifier
A device that amplifies light without converting it to electrical signal. Types include the EDFA, Raman, and SOA.

Optical attenuator
A passive component that produces controlled signal loss in an optical transmission line to decrease the optical power. Available as fixed or as variable types.

Optical carrier (OC)
Usually followed by a numerical designator such as 1, 12, 192, etc. Used in SONET and ATM transmission systems to describe the optical conversion of a synchronous transport signal at a specific rate, i.e., OC-3.

Optical circulator
A multiport device that steers optical energy between specific ports. Used in conjunction with a Bragg filter to provide OADM.

Optical Coating, AL-2233
ÅngströmLink® Teflon-like polymer suspended in an evaporative solvent that leaves behind an amorphous film when the solvent evaporates. Film thickness is controlled by the concentration of the dissolved polymer; standard concentrations create film thicknesses of 200nm to 10u; concentration is easily customized by the user to make any layer thickness in-between. Can be used for antireflection coating or low-surface energy masking (mold release).

Optical code division multiple access (OCDMA)
Creates a unique optical code, similar to a bar code, for each channel by selectively filtering out portions of the spectrum. This spectrally encoded light is then modulated with the data to be transmitted.

Optical Communication Cable
Fiber with a protective jacket.

Optical Conductors
Materials which offer a low optical attenuation to transmission of light energy.

Optical Connectors
See Fiber Optic Connectors.

Optical Cross Connection
See Fiber Optic Cross Connection.

Optical density (OD)
Used with laser protective eye wear. Optical density is the BASE-10 logarithm by a factor of 1000.

Optical distribution network (ODN)
The fibers, splitters, couplers, etc., in a passive optical network that provide the optical transmission means from the OLT to the users, and vice versa.

Optical Fiber
An optical waveguide comprised of a light-carrying core and cladding, which traps light in the core. Fiber optic communication systems use either single-mode or multimode types.

Optical Fiber Cable
An assembly consisting of one or more optical fibers.

Optical Fiber Duplex Adapter
A mechanical media termination device designed to align and join two duplex connectors.

Optical Fiber Duplex Connector
A mechanical media termination device designed to transfer optical power between two pairs of optical fibers.

Optical filter
A passive component used to modify the optical radiation that passes through it, usually by altering the spectral distribution. Employed to reject or absorb optical radiation in particular ranges of wavelength while transmitting it in other ranges. Tunable optical filters have the ability to track the signal wavelength variation over its operating wavelength range while untunable models have fixed values.

Optical Fluid, AL-52xx Series
ÅngströmLink® series of optically clear fluids used for refractive index matching between two optical elements. Good for laboratory applications and testing, when an easily reversible coupling is desirable.

Optical Interconnect
See Fiber Optic Interconnect.

Optical isolator (OI)
A nonreciprocal device intended to suppress backward reflections along an optical fiber transmission line while having minimum insertion loss in the forward direction.

Optical line terminal (OLT)
The PON controller card or unit located at the service provider. The laser at the OLT is frequently a DFB laser that transmits at 1490 nm or 1550 nm and is always on. Signals from the OLT tell the ONTs when to send upstream traffic to it. Several OLTs may be located in a single chassis.

Optical loss
The amount of optical power lost as light is transmitted through fiber, splices, couplers, etc. Also known as attenuation; measured in dB.

Optical loss test set (OLTS)
An measurement instrument for optical loss that includes both a meter and source.

Optical network terminal (ONT)
A media converter or gateway in the home. The ONT located either inside or outside the home or business converts the signals from light to electrical signals and contains ports to distribute signals on the existing home wiring (or wirelessly).

Optical Plastic, AL-62xx Series
ÅngströmLink® high purity, high refractive index, optically clear plastic. Moldable by conventional injection molding techniques. Optical transmission and environmental resistance equal to optical grade polycarbonate, with less stress birefringence than polycarbonate. Typically used for lenses in camera and video cell phones, and display backlights.

Optical Polyimide, AL-7254
ÅngströmLink® hybrid organic-inorganic polyimide composition capable of forming hard, durable, coatings on a wide variety of substrates. Coating is thermally and chemically stable, and ultra-hydrophobic.

Optical power
The amount of radiant energy per unit time, expressed in linear units of Watts or on a logarithmic scale, in dBm (where 0 dB = 1 mW) or dB* (where 0 dB*=1 microWatt).

Optical protection switch (OPS)
See bypass switch.

Optical receiver
An electronic device that converts optical signals to electrical signals.

Optical return loss, back reflection
Light reflected from the cleaved or polished end of a fiber caused by the difference of refractive indices of air and glass. Typically 4% of the incident light. Expressed in dB relative to incident power.

Optical signal-to-noise ratio (OSNR)
The difference between the signal being transmitted and the noise being created by an optical laser’s pulse. The higher the OSNR, the better the quality of service.

Optical Splice
See Fiber Optic Splice.

Optical supervisory channel (OSC)
A channel, accessed at each optical line amplifier site, used for maintenance purposes including but not limited to remote site alarm reporting, communications necessary for fault location, and orderwire. Not used to carry payload traffic.

Optical switch
A passive component possessing two or more ports that selectively transmits, redirects, or blocks optical power in an optical fiber transmission line.

Optical Time Domain Reflectometer (OTDR)
A device that uses an emitted light pulse of known power and width and measuring the light that is scattered back from events along the length of the fiber. Distance to splices, connectors, faults and the end of the cable can then be calculated and displayed.

Optical Transmitter
See Transmitter.

Optical Waveguide
Dielectric waveguide with a core consisting of optically transparent material of low attenuation (usually silica glass) and with cladding consisting of optically transparent material of lower refractive index than that of the core. It is used for the tra

Optical waveguide fiber
A high refractive index core with low refractive index cladding.

Optical-electrical-optical (OEO)
Specifies a network switch that receives an optical signal, and demultiplexes, switches, multiplexes and re-transmits the signal optically. Can perform 3R functions.

Optical-to-electrical (OE)
Shorthand notation for a point or device that converts an optical signal to an electrical signal.

Optoelectronic integrated circuit (OEIC)
Electronic and optoelectronic functions fabricated onto a single substrate by a monolithic process. May also include optical functions.

Optomechanical switch
Bipolar switch, based on moving fibers or mirrors, that moves optical signals between fibers.

Org
Generic top-level Internet domain name

Oscillatory Surge
A surge which includes both positive and negative polarity values.

Outer Conductor
The external conductive member in a coaxial structure, such as the housing in a coaxial connector.

Outgassing
1) De-aeration or other gaseous emission from a connector when exposed to heat, reduced pressure or both.  2) Percentage of a gas released during the combustion of insulation or jacketing material

Outlet
See telecommunications outlet.

Outlet Box, Telecommunications
A metallic or nonmetallic box mounted within a wall, floor or ceiling and used to hold telecommunications outlet/connectors or transition devices.

Outlet/Connector, Telecommunications
A connecting device in the work area on which horizontal cable terminates.

Outlets
A term used to describe the sockets provided in the work location of a Structured Cabling System. These are usually 8-pin modular sockets which can support a variety of services e.g. voice, video and data.

Output
The useful power or signal delivered by a circuit or device, or the terminals on the device from which the signal is extracted.

Output power
Radiant power, expressed in watts.

Outside diameter (OD)
A measurement of the diameter of ferrules, cables, ducts, and innerducts, e.g., 2.5 mm.

Outside Plant (OSP)
Telecommunications infrastructure designed for installation exterior to buildings. The portion of a communication network that exists mostly outdoors, but also between transmission sites. It includes patch panels, closures, pedestals, the media (e.g., fiber, twisted pair, coax) and the structure (aerial, underground, etc.) where the cable is installed and routed. The patch panels at each end are points of access for testing, as well as a point of separation of responsibilities for the transmission network.

Over Current
The current which causes an excessive temperature rise in a conductor.

Overall Diameter
Finished diameter over wire or cable.

Overbuild
Network deployment in an area that is served by an incumbent network operator. Although the services offered by the new provider may differ from those offered by the incumbent provider(s), some degree of competition is usually implicit.

Overcoat
Individual strands of tinned copper wire stranded together and then covered with a tin coating.

Overcoat Conductor
A stranded conductor made from individual strands of tin coated wire stranded together, and then given an overall tin coat.

Overcurrent
The current which causes an excessive temperature rise in a conductor.

Overfilled launch
A condition for launching light into the fiber where the incoming light has a spot size and NA larger than accepted by the fiber, filling all modes in the fiber.

Overfilled launch condition (OFLC)
When a light pulse floods the core of a fiber. Since LEDs produce erratic or incoherent burst of lights, they “overfill” the core when coupled to it.

Overlap
The amount the trailing edge laps over the leading edge of a spiral tape wrap.

Overload Capacity
The maximum level of current, voltage, or power which a device can withstand before it is damaged.

Oxidation
1) The addition of oxygen to a metal.  2) Any process where a metal loses electrons and is converted from a metal of zero electrical charge to a metallic ion with a positive charge.

Oxygen bomb test
A special aging test given to adhesives. Five hundred hours exposure to the condition in this test generally indicates whether a product will provide a good deal of service over a long range period of time.

Oxygen Index
Percentage of oxygen necessary to support combustion in a gas mixture. Flame retardant materials have a higher oxygen index.

Ozone
Reactive form of oxygen, typically found a round electrical discharges and present in the atmosphere in small quantities.

Ozone Index
Percentage of oxygen necessary to support combustion in gas mixture.

Ozone Test
Exposure of material to a high concentration of ozone to give an accelerated indication of oxidation in normal environments and in proximity to ozone producing apparatus.

Packet
A data unit of variable length used in communications protocols such as Ethernet and IP. Packets allow some flexibility by allowing more data to be sent without breaking it up into pieces and then re-assembling it at the receiver, in turn reducing overhead.

Packet switching
The transmission of packetized data through a network. Each packet has information linking it to the rest of the total message or file as well as the destination address. This form of communication is efficient because each packet can take a different route if necessary to maximize throughput.

Packet Switching Network
A network constructed to move data packets. An X.25 network is an example of a packet switching network.

Packing Fraction
The ratio of active cross-sectional area of fiber core, or cores, to the total end surface of the fiber or fiber bundle.

Paint Line
The line between a tape masked surface and a painted or otherwise treated surface.

Pair
Two wires forming a single circuit, held together by twisting, binding or a common jacket. Also known as a balance transmission line.

Paired Cable
Cable in which all conductors are arranged in color-coded pairs usually twisted around each other and then surrounded by a sheath.

Pairing
The union of two insulated single conductors through twisting.

Pan-tilt-zoom (PTZ)
The capability of a camera to move and scan the field of view. Pan refers to side-to-side movement, tilt refers to up/down movement, and zoom refers to the camera’s ability to zoom in or out on objects.

Panel
The side or front of a piece of equipment, usually metal, on which connectors are mounted.(MIL-STD)

Panel Mount
A connector designed to be fixed to a panel by means of screws or mounting nuts.

Panel Seal
A seal preventing the passage of moisture or gases through the gap between the mounting hole of the panel and the connector body of the fixed connector.

Parallel
A construction in which two or more conductors are laid parallel and surrounded and separated by an insulating material.

Parallel Cable
Two or more cables used to share the current in heavily loaded power circuits which permits the use of smaller conductors.

Parallel Digital
The processing and transmission of digital information in parallel information sets.

Parallel Heating
Radio Frequency Press configuration in which RF current is conducted along the glue lines in edge-gluing presses. The flow of the RF current is parallel with the glue lines.

Parallel Pair
A duplex construction of two insulated conductors laid parallel and then covered overall with a braid or jacket.

Parallel Splice
A parallel splice is a device for joining two or more conductors in which the conductors ie parallel and adjacent. See Lap Joint.

Parallel Stripe
A stripe applied longitudinally on a wire or cable parallel to the axis of the conductor.

Parallele Data
Multiple bits of data transmitted each on its own line simultaneously.

Parasitic Capacitance
The capacititive leakage across a component such as a resistor inductor, filter, isolation transformer or optical isolator that adversely affects high-frequency performance.

Parity Check
The addition of a bit to a character to aid in error checking.

Part 15
A Federal Communications Commission ruling which defines the parameters for use of the industrial-scientific-medical bands in the US (such as low-power output, spread spectrum, non-interference, etc.)

Passive
A component that requires no electrical power to operate, i.e., optical splitters, wavelength division multiplexers, filters, circulators, and optical attenuators.

Passive dispersion compensator
A passive component used to compensate the chromatic dispersion of an optical path. Can use dispersion compensating fiber or Bragg filters.

Passive optical network (PON)
A point-to-multipoint system, specified by the ITU, IEEE, and SCTE, that is made up of fiber optic cabling, passive splitters and WDMs that distribute an optical signal from the service provider to homes (FTTH) or buildings (FTTB).

Passive Tag
An RF identification transponder that does not have an internal power source. Their energy source is the power emitted from an antenna.

Paste
An adhesive composition having a characteristic plastic-type consistency, that is, a high order or yield value, such as that of a paste prepared by heating a mixture of starch and water and subsequently cooling the hydrolyzed product

Patch Cable
A cable with plugs or terminals on each end of the conductors to temporarily connect circuits of equipment together. In the IBM Cabling System, a length of Type 6 cable with data connectors on both ends.

Patch Cord
A length of cable with connectors on one or both ends used to join telecommunications links/circuits at the cross-connect .

Patch Cord Cable
Bulk cable used in the manufacture of patch cords.

Patch Panel
Distribution area to rearrange fiber connections and circuits.

Patchcord
A fixed length of cable with like connectors on both ends (or, in the case of a hybrid cable, different connectors). Sometimes called a cable assembly, patch cable or jumper.

Pathway(s)
Designated cable routes and/or support structures in a false floor or ceiling.

Pay-Off
The process of feeding a cable or wire from a bobbin, reel, or other package.

PCT
Passive Component Tester, application that runs on MAP

Peak
The maximum instantaneous value of a varying current or voltage.

Peak Load
Maximum force recorded during a strength test.

Peak Voltage
The maximum instantaneous voltage

Peel adhesion
The force per unit width, typically expressed in oz/in width (US), required to break the bond between a tape and a surface when peeled back usually at 180 degrees at a standard rate and condition. See peel test.

Peel strength
The average load per unit width of bondline required to separate progressively a flexible member from a rigid member or another flexible member.

Peel test
A test of an adhesive or sealant using one rigid and one flexible substrate. The flexible material is folded back (usually 90 or 180 degrees) and the substrates are peeled apart. Strength is usually measured in pounds per inch of width (PLI).

Peening
Permanent distortion of outside wire in a rope caused by pounding

Pendent group
Side group an offshoot, neither oligomeric nor polymeric, from a chain. (IUPAC)

Penetration
The entering of an adhesive into an adherend. Discussion—This property of a system is measured by the depth of penetration of the adhesive into the adherend.

Percent Conductivity
Conductivity of a material expressed as a percentage of that of copper.

Percent moisture content
Percent moisture content is equal to the weight of water divided by the weight of bone dry wood x 100.

Percent Plating
Quantity of plating on a conductor expressed as percentage by weight; thus, for the same percentage, as the conductor diameter increases, so does the thickness of the plating.

Percent Solids
The percentage of non-volatile material contained in a liquid.

Percent Volatile
Percentage of a liquid or solid by volume that will evaporate at ambient temperature.

Percentage Conductivity
Conductivity of a material expressed as a percentage of that of copper. Also used to indicate ratio of conductance between the phase conductor and the neutral in power cables.

Periodic copolymer
A copolymer consisting of macromolecules comprising more than two species of monomeric units in regular sequence. (IUPAC)

Periodic copolymerization
A copolymerization in which a periodic copolymer is formed. (IUPAC)

Periodicity
The uniformly spaced variations in the insulation diameter of a transmission cable that result in reflections of a signal, when its wavelength or a multiple thereof is equal to the distance between two diameter variations.

Peripheral Seal
A seal provided around the periphery of connector inserts to prevent the ingress of fluids or contaminants at the perimeter of mated connectors.

Peripheral(s)
Additions to a system, a resource e.g. printer, scanner, etc.

Permanence
Resistance to appreciable changes in characteristics with time and environment.

Permanent link
The transmission path between two mated interfaces of generic cabling, excluding equipment cables, work area cables and cross-connections.

Permanent set
The amount of deformation that remains in a sealant or adhesive after removal of a load.

Permeability
The extent to which a material can be magnetized; often expressed as the parameter relating the magnetic-flux density induced by an applied magnetic-field intensity.

Permeability (magnetic)
The measure of how much better a material is than air as a path for magnetic lines of force. Air is assumed to have a permeability of 1.

Permittivity
The ratio of the capacitance of a condenser with dielectric between the electrodes to the capacitance when air is between the electrodes. Also called Permittivity and Specific Inductive Capacity (SIC).

Permittivity Relative
Synonym term for relative dielectric constant.

Peroxide
A molecule with an unstable -O-O- bond (Example: HOOH)

Perpendicular Heating
Radio Frequency Press configuration in which RF current is conducted through a plywood panel resulting in mass heating. The flow of current is perpendicular to the glue lines.

Personal Communications Services (PCS)
Federal Communications Commission terminology for two-way, personal, digital wireless communications systems.

Personal Digital Assistant (PDA)
A portable computing device that is capable of transmitting data. PDAs can be used for paging, data messaging, electronic mail, receiving stock quotations, personal computing, facsimile, and as a personal electronic organizer.

Personal Handyphone System (PHS)
Japan’s designation for its digital cordless telephony standard.

Pertaining to a device that responds to optical power, emits or modifies optical radiation, or utilizes optical radiation for its internal operation.

Phase
A particular stage or point of advancement in an electrical cycle. The fractional part of the period through which the time has advanced, measured from some arbitrary point. Usually expressed in electrical degrees where 360 degrees represent one cycle.

Phase Shift
Change in phase of a voltage or current after passing through a circuit or cable.

Phase Stability
Variation of the electrical length of a cable that can result from temperature or mechanical stress due to bending or torsion.

Phenolic resin
A thermosetting resin. Usually formed by the reaction of a phenol with formaldehyde.

Phosphor Bronze
This strong and relatively hard alloy is used to fabricate metal parts and springs. Phosphor bronze is resistant to corrosion.

Photodetector
An electro-optic device that transforms light energy into electrical energy.

Photodiode
A semiconductor that converts light to an electrical signal, used in fiber optic receivers.

Photon
A quantum of electromagnetic radiation, a unit of light. Light can be viewed as a series of photons.

Photonic integrated circuit (PIC)
A collection of photonic components monolithically integrated to perform a function.

Physical Contact (Fiber Optic)
Abbreviated as PC, this is a design feature of fiber optic connectors, where the mating contacts' faces are in contact and under pressure provided by springs, resulting in lower loss.

Physical contact (PC)
Refers to the endface polish of a ferrule. Designed to lower reflections by changing the spherical or angle at the end of a ferrule and its internal fiber. Variations include PC, super PC (SPC), ultra PC (UPC), and angled PC (APC).

Physical Cure
Cure by applied heat or evaporation. Discussion -- Physically curing adhesives are already present in their final chemical state upon application.

Physical Layer
Layer 1 of the open systems interconnection (OSI) model. The physical layer protocol is the hardware and software in the line terminating device which converts the databits needed by the datalink layer into the electrical pulses, modem tones, optical signals or other means which will transmit the data.

Physical State
The condition of a material – solid, liquid or gas at room temperature.

Physical Topology
Physical cabling layout i.e. ring, bus, star wired etc.

PIC Code
Pre-subscribed/Primary Inter-LATA Carrier Code

Pick
Distance between two adjacent crossover points of braid filaments. The measurement in picks per inch indicates the degree of coverage.

Pick-up roll
A spreading device where the roll for picking up the adhesive runs in a reservoir of adhesive.

Picks Per Inch
The number of times the carriers in a braid cross over each other in the same direction along the longitudinal axis for each inch of length.

Pico
One-millionth of one-millionth (10-12).

Picocell
A cell site for a personal-communications-services network that is somewhat smaller than a microcell and often used to provide service within large buildings and malls.

Picofarad (pF)
One trillionth of a farad. A unit capacitance usually used to designate capacitance unbalance between pairs and capacitance unbalance of the two wires of a pair to ground. (abbreviation pf)

Pigtail
A fiber optic connector that is terminated to one end of an optical fiber cable. A short length of optical fiber, permanently fixed to a component, used to couple power between the component and a transmission fiber.

Pigtail Orientation
A pigtail may be approximately perpendicular to the axis through the center of the coil of a cordset, and this is referred to as a dropped pigtail or perpendicular pigtail. A pigtail may be approximately parallel to the axis through the center of the coil and this is referred to as a turned out pigtail or an axial pigtail.

Pigtail Wire
Fine stranded, extra flexible, rope lay lead wire attached to a shield for terminating purposes.

Pin
A conductor on a plug or connector.

Pin and Sleeve
Common term in reference to an IEC60309 device Outbound Link.

Pin Contact
A contact having an engagement end that enters the socket contact. (MIL-STD) A male type contact, usually designed to mate with a socket or female contact. It is normally connected to the “dead” side of a circuit.

PIN diode
Positive intrinsic negative diode, a type of photodiode used to convert optical signals in a receiver. Can be used with both analog and digital systems.

Pinholes
Small holes visible on the surface of soldered joints, which generally indicate the presence of a larger void within the joint. Typically caused by the generation of gas during solidification due to presence of salts and water. Sometimes called blowholes.

Pitch
(1) In flat cable, the nominal distance between the index edges of two adjacent conductors. (2) The nominal center-to-center distance of adjacent conductors. (When the conductors are of equal size and thier spacing is uniform , the pitch is usually measured from the reference edge of the adjacent conductors.)

Pitch Diameter
Diameter of a circle passing though the center of the conductors in any layer of a multi-conductor cable.

Pitting
An unacceptable polishing condition usually caused by the contamination of the lapping film from a combination of fiber optic and grit particles.

Plain Conductor
A conductor consisting of only one metal.

Plain old telephone service (POTS)
Basic telephone service, dial tone without special features.

Plain Weave
A weave used on woven cables. Threads between the wires act as binders and give the cable lateral stiffness and linear flexibility. Also called Standard and Square Weave.

Planar lightwave circuit (PLC)
A technology that enables photons to pass through a wafer structure in much the same way they do through fiber. It has become an accepted technology for WDM systems, largely in the form of multiplexer/demultiplexer modules based on arrayed waveguide gratings.

Planar waveguide
A waveguide formed on the surface of an optically flat material where the area of propagation has a high refractive index and guides light in the same manner as optical fiber. When utilizedin couplers or splitters, the waveguide is divided from a single input into multiple outputs.

Planetary Cabler
A cabling machine whose payoff spools are mounted in rotating cradles that hold the axis of the spool in a fixed direction as the spools are revolved about one another so the wire will not kink as it is twisted.

Planetary Twister
A twisting machine whose payoff spools are mounted in rotating cradles that hold the axis of the spool in a fixed direction as the spools are revolved about one another so the wire will not kink as it is twisted.

Plastic
High polymeric substances, including both natural and synthetic products, but excluding the rubbers that are capable of flowing under heat and pressure.

Plastic Clad Silica (Fiber Optic)
A fiber structure where the cladding around the core is a soft plastic, abbreviated PCS.

Plastic Deformation
Change in dimensions under load that is not recovered when the load is removed.

Plastic Fiber
An optical fiber made of plastic alone.

Plastic optical fiber (POF)
An optical fiber type in which both the core and cladding are made from plastic. Their transmission is typically much poorer than glass fiber, and their lowest losses are in the visible region. GI-POF is the high bandwidth version using a graded index core.

Plastic-clad silica fiber
A fiber composed of a silica glass core with a transparent plastic cladding.

Plasticity
A property of adhesives that allows the material to be deformed continuously and permanently without rupture upon the application of a force that exceeds the yield value of the material.

Plasticizer
A material incorporated in an adhesive to increase its flexibility. The addition of the plasticizer may cause a reduction in melt viscosity, lower the temperature of the second-order transition, or lower the elastic modulus of the solidified adhesive.

Plastisol
A physical mixture of resin (usually vinyl) compatible plasticizers and pigments. Mixture requires fusion at elevated temperatures in order to convert the plastisol to a homogeneous plastic material.

Plate Current Meter
An electrical meter placed in the grid circuit of a RF generator to measure electrical current.

Plated Through Hole
A hole through a Printed Circuit Board that has been electroplated and into which a lead is placed and soldered for electrical and mechanical connection.

Plating
The overlaying of a thin coating of metal on metallic components to improve conductivity, provide for easy soldering or prevent rusting or corrosion. (MIL-STD)

Plenum
The air handling space such as that found above drop-ceiling tiles or in raised floors. It is also the most stringent fire code rating for indoor cables.

Plenum Cable
Cable approved by Underwriters Laboratories for installation in plenums without the need for conduit.

Plug
A device used for connecting wires to a jack. It is typically used on one or both ends of equipment cords or on wiring for interconnects or cross connects.

Plug Connector
An electrical fitting with pin, socket or pin and socket contacts, constructed to be affixed to the end of a cable, conduit, coaxial line cord or wire for convenience in joining with another electrical connector and not designed to be mounted on a bulkhead, chassis or panel. (MIL-STD)

Ply
The number of individual strands or filaments twisted together to form a single thread.

Point
An electrical contact used for testing.  Each pin of the test connectors of the tester can be considered a point.  Likewise each connector pin on the DUT or mating connectors can be considered a point.

Point of presence (POP)
The physical location where a long-distance carrier terminates lines before connecting to the local exchange company, another carrier, or directly to a customer.

Point to Point Wiring
An interconnecting technique wherein the connections between components are made by wires routed between connecting points.

Point-to-multipoint (P2MP)
A star topology with optical splitters for PON systems in which an OLT is optically linked to multiple ONTs through entirely passive means.

Point-to-point (P2P)
A topology in which all fiber links are from one transmitter to one receiver. Branching can be done at an intermediate point via an active device located anywhere on the network, including the CO or a curb-side enclosure. For FTTx installations, it is typically used in active Ethernet.

Point-to-Point Wiring
An interconnecting technique wherein the connections between components are made by wires routed between connecting points.

Poise
Measure of viscosity (in cgs units).

Poke Home Contact
Term applied to a male or female contact to which a wire has been permanently affixed prior to the assembly of the contact into the insert. A registered trade name of Amphenol.

Polarity
In electricity, the quality of having two oppositely charged poles, one positive one negative. 

Polarization
Mechanical arrangement of keyways, inserts or grooves in a connector shell or insert that allows connectors of the same configuration to be used without the danger of interconnection to the wrong mating connector. Also called Keying

Polarization mode dispersion (PMD)
Typical single-mode fibers support two perpendicular polarizations of the original transmitted signal, which may travel at different speeds and arrive at different times. The average difference in arrival times of the two polarization modes, normalized with length, is referred to as PMD.

Polarization Slot
A slot in the edge of a printed board that is used to assure the proper insertion and location of the board in a mating connector. (See also "Keying Slot" )

Polarize
The arrangement of mating connectors such that the connector can be mated in only one way. (MIL-STD)

Polarized
A plug and connector formed in a way that only allows proper connection.

Polarized dispersion loss (PDL)
The difference in dB between the maximum and minimum values of loss (attenuation) due to variation of the polarization states of light propagating through a device. The ITU defines PDL as polarization dependent loss, the maximum variation of insertion loss due to a variation of the state of polarization (SOP) over all SOPs.

Polarizing Pin, Key or Keyway
A device incorporated in a connector to accomplish polarization. (MIL-STD)

Polishing
Act of smoothing ends of fibers to an optically smooth finish, generally using abrasive.

Polishing (Fiber Optic)
The act of smoothing ends of fibers to an "optically smooth" finish, generally using abrasives. Optically smooth surfaces allow maximum transmission of light between fibers at connections, and minimize coupling loss.

Polishing paper
See lapping film.

Polishing puck
A fixture manufactured to hold the fiber optic connector ferrule perpendicular to a lapping film surface while polishing the fiber optic endface.

POLL
In LAN applications, it is a query to a node looking for information to be transferred on the network.

Polyaddition
A polymerization in which the growth of a polymer chain proceeds by addition reactions between molecules of all degrees of polymerization, not accompanied by the formation of low-molar-mass by-product(s). (IUPAC)

Polyamide
A polymer formed by the reaction of a diamine and a diacid. Nylons are commercial polyamides characterized by toughness, solvent resistance and sharp melting point.

Polybutadiene
A type of synthetic rubber often blended with other synthetic rubbers to improve their properties.

Polychloroprene
Chemical name for Neoprene. A rubber-like compound used for jacketing where wire and cable will be subject to rough usage, moisture, oil, greases, solvents and chemicals. May also be used as low insulating material.

Polycondensation
a polymerization in which the growth of a polymer chain proceeds by condensation reactions between molecules of all degrees of polymerization accompanied by the formation of low-molar-mass by-products(s). The growth steps are expressed by P_x+P_y -> P_x+y + L {x} element of {1, 2, ... ?}; {y} element of{1, 2, ...?} where P_x and P_y denote chains of degree of polymerization x and y, respectively, and L a low-molar-mass by-product. In a polycondensation where the total amounts of the monomers are present from the beginning of the polymerization, the average degree of polymerization increases with conversation of reactive groups. (IUPAC)

Polyelectrolyte molecule
a macromolecule which in an ionising solvent may dissociate to give ions. (IUPAC)

Polyerm
A material of high molecular weight formed by polymerization of lower molecular weight molecules.

Polyester
Polyethylene terephthalate which is used extensively in the production of a high strength moisture resistant film used as a cable core wrap (see Mylar). A resin formed by the reaction between a dibasic acid and a hydroxy alcohol. Polyethylene terephthalate, used extensively as a moisture resistant cable conductor wrap.

Polyethylene (PE)
A thermoplastic used to jacket aerial and direct buried cables.

Polyhalocarbon
A general name for polymers containing halogen atoms. The halogens are fluorine, chlorine, bromine and iodine.

Polymer
A substance made of many repeating chemical units or molecules. The term polymer is often used in place of plastic, rubber or elastomer. A giant molecule formed when hundreds or thousands of small monomer molecules bond to each other to form chains or networks

Polymer Distribution Graph
A graph that shows the relative amounts of chains of different lengths during the progression of a polymerization

Polymer-solvent interaction
The sum of the effects of all intermolecular interactions between polymer and solvent molecules in solution that are reflected in the Gibbs and Helmholtz energies of mixing. (IUPAC)

Polymerization
Chemical reaction in which one or more small molecules combine to form larger molecules.

Polymers
Substance made up of many units such as polyethylene, polystyrene, etc.

Polyolefin
A family of thermoplastics based upon the unsaturated hydrocarbons known as olefins. When combined with butylene or styrene polymers, they form compounds such as polyethylene and polypropylene.

Polypropylene
A thermoplastic similar to polyethylene but stiffer and having higher softening point (temperature); excellent electrical properties.

Polystyrene
A polymer commonly used in packaging.

Polytetrafluoroethylene (PTFE)
This is the most thermally stable and chemically resistant of all carbonaceous insulating compounds. It is unaffected by sunlight, moisture, and practically all chemicals. Temperature range is -90° to 250° C and electrical properties are very constant over the temperature range and a wide range of frequencies.

Polyurethane
Broad class of polymers noted for good abrasion and solvent resistance. Can be solid or cellular form.

Polyvinyl acetate (PVA) glue
Any glue consisting chiefly of polyvinyl acetate polymer. This category includes both traditional white glues and yellow aliphatic resin glues. Although PVA glues can vary in strength, flexibility, water resistance, heat resistance and sandability, they are generally non-toxic. All PVA glues are prone to “creep” or slowly stretch under long term loads, and are not recommended for structural applications.

Polyvinyl acetate emulsion adhesive
A latex adhesive in which the polymeric portion comprises polyvinyl acetate, copolymers based mainly on polyvinyl acetate, or a mixture of these, and which may contain modifiers and secondary binders to provide specific properties.

Polyvinylchloride (PVC)
A thermoplastic material composed of polymers of vinyl-chloride which may be rigid or elastomeric, depending on specific formulation.

Polyvinylidene fluoride (PVDF)
A dielectric fluoropolymer that is resistant to corrosive chemicals and radiation. Used to jacket stranded cable.

Porosity
Multiple air voids in an insulation or jacket wall.

Port
The cable terminations in the equipment system at which various types of communications devices, switching equipment, and other devices are connected to the transmission network.  1) A functional unit of a node through which data can enter or leave a data network.  2) In data communications, that part of a data processor which is dedicated to a single data channel for the purpose of receiving data from or transmitting data to one or more external, remote devices.  3) An access point for data entry or exit.

Portable Power Cable
Flexible, all rubber insulated for hard usage. Some cables have shielded conductors (metallic or non-metallic) and can have neoprene sheath overall.

Ports
A computer interface capable of transmitting and or receiving information.

Positioner
A device that is attached to a crimping tool and locates the contact in the correct location for crimping. It is usually interchangeable with other positioners. (MIL-STD)

Post cure
A treatment (normally involving heat) applied to an adhesive assembly following the initial cure to modify specific properties.

Post Insulate
To insulate a connection after assembly.(MIL-STD)

Postcure
After the initial cure, to further treat an adhesive by time or temperature, or both, to modify specific properties.

Pot life
The useable life of a synthetic resin mix after a catalyst or hardener has been added.

Potentiometer
A variable resistor often used to control a circuit. 

Potting
1) The permanent sealing of the cable end of a connector with a compound or material to exclude moisture and/or provide a strain relief.(MIL-STD)   2) The sealing of a cable termination or other component with a liquid which thermosets into an elastomer.

Potting Compound
A material, usually organic , tha is used for the encapsualtion of components and wires.

Potting Cup
An accessory which, when attached to the rear of a plug or receptacle, provides a pouring form for potting the wires at the wire entry end of the connector.

Potting Form
Not preferred. See Mold, Potting, Electrical Connector.

Power
The rate at which energy is transferred.

Power budget
The difference (in dB) between the transmitted optical power (in dBm) and receiver sensitivity (in dBm).

Power Cables
Cables of various sizes, construction, and insulation, single or multi-conductor, designed to distribute primary power to various types of equipment.

Power Contact
Type of contact used in multi-contact connectors to support the flow of rated current.

Power Factor (Fp)
The ratio of resistance to impedance. The ratio of an actual power of an alternating current to apparent power. Mathematically the cosine of the angle between the voltage applied and the current resulting.

Power Handling Capacity
The average power which a cable can handle without exceeding its maximum operating temperature.

Power Loss
The difference between the total power delivered to a circuit, cable or device and the power delivered by that device to a load.

Power meter
Test equipment that measures the optical power (dBm) and attenuation (dB) in a fiber optic connector, fiber optic cable, or fiber optic system.

Power Ratio
The ratio of power appearing at the load to the input power. Expressed in dB, it is equal to 10 log10 (P2/P1) where P1 is input power and P2 is the power at that load.

Power Sum
A method of testing and measuring crosstalk in multi-pair cables that accounts for the sum of crosstalk affecting a pair when all other pairs are active. This is the only method of specifying crosstalk performance that is suited to cables with more than four pairs.

Power Sum Attenuation to Crosstalk Ratio (PSACR)
A ratio expressed in dB, determined by subtracting the insertion loss from the POWER SUM NEAR-END CROSS TALK LOSS.

Power Sum Equal Level Far-End Crosstalk (PSELFEXT)
A computation of the unwanted signal coupling from multiple transmitters at the near-end into a pair measured at the far-end relative to the received signal level on that same pair.

Power Sum Near-End Crosstalk Loss (PSNEXT)
A computation of the unwanted signal coupling from multiple transmitters at the near-end into a pair measured at the near-end.

Praseodymium-doped fiber amplifier (PDFA)
A high gain (30 dB), high saturation (+20 dBm) amplifier that operates in the O-band.

Pre-Bond
Stranded wire which has been fused, topcoat tinned, or overcoat tinned.

Pre-bond treatment
Synonym for surface preparation.

Pre-Insulate
The insulation of a connector prior to assembly of the contact or termination of the conductor.(MIL-STD)

Pre-Tinned
Solder applied to either or both the contact and conductor prior to soldering. (MIL-STD)

Pre-Tinned Solder Cup
Solder cups whose inner surfaces have been pre-coated a small amount of tin lead solder.

Pre-Wiring
The practice of concealing station wire or cable in the walls of buildings while they are being constructed. It is cheaper and more satisfactory for the owner.

Precious Metal
One of the relatively scarce and valuable metals; gold, silver and the platinum group metals.

Preece Test
A recognized standard of testing the galvanized coating on wire

Preform
A glass structure from which an optical fiber waveguide can be drawn.

Preformed Strand
Strand in which the wires are permanently shaped, before fabrication in the strands, to the helical form they assume in the strand

Preformed Wire Rope
Wire rope in which the strands are permanently shaped, before fabrication into the rope, to the helical form they assume in the wire rope

Premises
Defined as the subscriber’s home or place of business. In a multiple dwelling unit, each apartment is counted as one.

Premises Distribution System (PDS)
The transmission network inside a building or group of buildings that connects various types of voice and data communication devices, switching equipment, and information management system together, as well as to outside communications networks. It includes the cabling and distribution hardware components and facilities between the point where building wiring connects to the outside network lines, back to the voice and data terminals in to office or other work locations. The system consists of all the transmissions media and electronics, administration points, connectors, adapters, plugs, and support hardware between the building's side of the network interface and the terminal equipment required to make the system operational.

Preproduction test
A test or series of tests conducted by (1) an adhesive manufacturer to determine conformity of an adhesive batch to established production standards, (2) a fabricator to determine the quality of an adhesive before parts are produced, or (3) an adhesive specification custodian to determine conformance of an adhesive to the requirements of a specification not requiring qualification tests.

Presentation Layer
Layer 6 of the OSI model. Responsible for identifying the syntax of the data being transmitted.

Press Fit Contact
An electrical contact which can be pressed into a hole in an insulator, printed board, with or without plated through-holes, or a metal plate.

Pressure-sensitive adhesive (PSA)
A viscoelastic material which in solvent-free form remains tacky and will adhere instantaneously to most solid surfaces with the application of very slight pressure.

Pressure-sensitive article
A combination of a pressure-sensitive adhesive with a backing or with a backing and release liner. Discussion—Examples of such articles include tapes, labels, stickers and handspreads; transfer failure --in characterizing the locus of failure in a pressure-sensitive article, separation at the interface of adhesive and backing.

Pressurization
The use of pressurized gas or dry air inside Air Core cables to prevent the entry of water at faulty splices or minor sheath cracks. It can also trigger an alarm when major faults occur and can assist in locating the damaged areas.

Prestretching
Stressing a wire rope or strand before use under such a tension and for such a time that the constructional stretch is largely removed

Prevailing Torque
Measurement of average force needed to provide continuing movement, after unseating, through first full turn.

Primary
The transformer winding which receives the energy from a supply circuit.

Primary Coating
The plastic coating applied directly to the cladding surface of the fiber during manufacture to preserve the integrity of the surface.

Primary Insulation
The first layer of non-conductive material applied over a conductor, whose prime function is to act as electrical barrier (sic…insulation).

Primary Protection
The minimum protection required on all exposed facilities to comply with NEC requirements.

Primary Rate Interface (PRI)
ISDN standard interface comprising 23 B + 1 D channel for North America, and 30 B + 1 D Channel for Europe. See Basic Rate Interface (BRI) and Integrated Services Digital Network (ISDN). The North American 1.544 Mb/s T1 (23B+D) or European 2.048 interface (PRI) Mb/s E1 (30B+D) ISDN interface typically used to connect ISDN PBXs to the public ISDN.

Primary Wiring
A printed circuit intended to provide point-to-point electrical connections.

Primer
A coating applied to a surface, prior to the application of an adhesive, to improve the performance of the bond.

Primer, Surface
A surface primer is a coating that changes the character of a surface so that an adhesive or coating will adhere to it more effectively.

Priming
Applying a coating to improve the performance of the bond; in pressure sensitive tapes, coating the backing on the adhesive side with a thin layer of adhesive-like material, which serves as a bonding agent between the adhesive and the backing.

Printability
The ability of a tape to accept and hold a printed legend, and especially to resist offset of the printing when rewound into a roll after printing.

Printed Circuit
This term is in common use with at least two meanings: 1) A generic term to describe a printed board produced by any of a number of techniques used to fabricate electrical interconnect systems. 2) A circuit obtained by printing and comprising printed components.

Printed Circuit Board (PCB)
An epoxy glass and metal composite on which circuits are etched and to which active, passive and hardware components are attached. Also called a PCB or PC board.

Printed Wiring
A printed circuit intended to provide point-to-point electrical connections.

Private Branch Exchange (PBX)
A private switching system usually serving an organization, such as a business or government agency, and located on the customer's premises. It switches calls both inside a building or premises and outside to the telephone network, and can sometimes also provide access to a computer from a data terminal.

Profile alignment system (PAS)
A core alignment technique for fusion splices in which light is injected at right angles. A CCD camera detects the fiber’s refractive inlet profile in the X and Y axes for optimization.

Profile dispersion
Difference between maximum refractive index in the core and maximum refractive index in the cladding.

Programming
Ability to select various circuit patterns by interconnecting appropriate contacts on one side of a connector plug or panel.

Proof Load
A load applied in performance of a proof test. Typically 40-60% of breaking strength

Proof Test
Non-destructive test to verify construction and workmanship of a wire rope assembly

Propagation
Delay time required for an electrical wave to travel between two points on a transmission line. The step an addition polymerization in which a monomer is added to the growing polymer chain

Propagation Delay
Propagation Delay is the time it takes for a signal to propagate from one end of a conducting pair in cabling, cables or connecting hardware to the opposite end of that pair. (also see DELAY SKEW).

Propagation Rate
The speed at which electricity travels in a transmission medium. Expressed as a percentage of the speed of light that is represented as a lowercase "c".

Propagation Time
Time required for an electrical wave to travel between two points on a transmission line.

Proportional limit
The maximum stress that a material is capable of sustaining without significant deviation from proportionality of stress to strain.

Proprietary Networks
Networks that are not designed, installed to any standard based guidelines and do not relate specifically to any relevant standard.

Proprietary Systems
Systems that are not Standards specific and therefore inoperable with standards based equipment.

Protocol
A set of rules governing all aspects of communicated data. A standardized set of communications conventions enabling the orderly and accurate transfer of data between stations.

Protocol Analyzer
A device capable of capturing, monitoring, decoding and analyzing various communications protocols. A high level troubleshooting and analysis tool.

Prototype
A model suitable for use in the complete evaluation of form, design and performance.

Protrusion
According to the TIA, the fiber optic is either polished even with the endface or has a positive or negative protrusion, i.e., “sticks out” or is recessed.

Proximity Effect
Non-Uniform current distribution over the cross-section of a conductor caused by the variation of the current in a neighboring conductor.

Pseudo-cooligomer
An irregular oligomers, the molecules of which are derived from one species of monomer but for which one finds it convenient to use co-oligomer terms. (IUPAC)

Pseudo-copolymer
An irregular polymer, the molecules of which are derived from one species of monomer but for which one finds it convenient to use copolymer terms. Where appropriate, adjectives specifying the types of "copolymer" may be applied to "pseudo-copolymer". The term statistical pseudo-copolymer, for instance, may be used to describe an irregular polymer in the molecules of which the sequential distribution of configurational units obeys known statistical laws. (IUPAC)

Public Branch Exchange (PBX)
A telephone switching system designed to serve as a control and to route calls in large multi-phone environments, such as offices. Most PBXs can handle custom features for users’ specific telecom requirements.

Public Network Interface
A point of demarcation between public and private network. In many cases the public network interface is the point of connection between the network provider's facilities and the customer premises cabling.

Public Switched Telphone Network (PSTN)
A landbased telecommunications system where cellular calls are routed.

Pull Box
A device to access a raceway used to facilitate placing of wire or cables.

Pull Cord/Pull Wire
Cord or wire placed within a raceway and used to pull wire and cable through the raceway.

Pull point
A physical location where optical cable can be accessed and pulled, reducing friction and damage, and allowing for longer installed spans.

Pull Strength
The maximum pulling force that can be safely applied to a cable without damage.

Pull Tension
The maximum pulling force that can be safely applied to a cable without damage.

Pull-Out Force
Force necessary to separate a conductor from a contact or terminal, or a contact from a connector by exerting a tensile pull. (MIL-STD)

Pulling Eye
A device which may be fastened to the conductor or conductors of a cable or formed by or fastened to the wire armor and to which a hook or rope may be directly attached in order to pull the cable into or from a duct.

Pulling Tension
The amount of pull, measured in pounds, placed on a cable during installation.

Pulse
A current or voltage which changes abruptly from one value to another and back to the original value in a finite length of time. Used to describe one particular variation in a series of wave months.

Pulse Broadening
An increase in pulse duration resulting in optical dispersion.

Pulse Cable
A type of coaxial cable constructed to transmit repeated high voltage pulses without degradation.

Pulse code modulation (PCM)
A coding scheme for converting analog signals into a digital bit stream.

Pulse Spreading
The dispersion of incoming optical signals along the length of an optical fiber.

Pulse Width
The length of time that the pulse voltage is at the transient level. Electronic pulse widths are usually in the millisecond, microsecond or nanosecond range.

Pulsed Lasers
Lasers that emit energy in a series of short bursts, or pulses, and are inactive between each pulse. They typically deliver several watts of peak power per pulse.

Punch-Down
A method of securing a wire to a wiring terminal. The insulated wire is placed in the terminal groove and pushed down with a special tool. As the wire is seated, the terminal cuts through the insulation to make an electrical connection, and the spring-loaded blade of the tool trims the wire flush with the terminal. Also called Cut-Down.

Punch-Down Block
A device used to terminate and cross-connect premises wiring. (also see also CONNECTING BLOCK)

PUR (Polyurethane)
Thermoplastic polymer used for cables as an extruded jacket. Exhibits extreme toughness and abrasion resistance. It is flexible to below -50°C.

Push/pull
Connector clip or locking device that holds the connector in a socket or interface. Uses a “push then pull” coupling technique. SC, LC, and MPO/MTP are common types of connectors using a push/pull coupling mechanism.

Put-Up
Refers to the packaging of wire and cable. The term itself refers to the quantity of product that is ready to be stored or shipped.

PVC (Polyvinyl Chloride)
The material most commonly used for the insulation and jacketing of cable.

Pyrometer
One of several devices designed to measure surface temperature.

Quad
A series of four separately insulated conductors, generally twisted together in pairs. Also, a series-parallel combination of transistors with increased reliability because failure of one transistor will not disable the entire circuit.

Quad Fiber Cable
A type of fiber optic cable that has four single cables enclosed in an extruded jacket of polyvinyl chloride (PVC), with a rip cord for pulling back the jacket to access the fibers.

Quadders
Three-bay machines which can twist four wires together and cable braided and shielded wires with varying lay lengths.

Quadplexer
Commonly known as a passive WDM, this transceiver package performs four multiplexing or demultiplexing functions. Used in 10 Gigabit OLTs when coexisting with legacy PON systems.

Quadrax
An abbreviation of quadraxial, a concentric cable having a center conductor, two intermediate conductors, and an outer shield, all separated by insulation.

Qualification test
A series of tests conducted by the procuring activity, or an agent thereof, to determine conformance of materials, or materials system, to the requirements of a specification which normally results in a qualified products list under the specification.

Quality of service (QoS)
A measure of the telephone service quality provided to a subscriber.

Quasi-single-strand chain
a chain that comprises constitutional units joined to each other through one single atom on only one of the units. Quasi-single-strand chains are not single-strand chains, but they can be named in the same manner. (IUPAC)

Quick Disconnect
A type of connector or splice which permits rapid locking and unlocking of mating parts.(MIL-STD)

Quick stick
Also known as quick tack, finger tack, initial adhesion, wet grab -- the property of a pressure sensitive adhesive which allows it to adhere to a surface under very light pressure; it is determined by the ability of the adhesive to quickly wet the surface contacted.

Raceway
Any channel designed for holding wires or cables, i.e. conduit, electrical metallic tubing, sleeves, slots, underfloor raceways, cellular floors, surface raceways, lighting fixture raceways, wireways, cable troughs, busways, auxiliary gutters, and ventila

Rack
A type of structure used to house electronic components which permits convenient removal of portions of equipment. (MIL-STD)

Rack and Panel
The type of connector that is attached to a panel or side of equipment so that when these members are brought together, the connector is engaged.

Rack unit (RU)
A measurement of vertical space in an equipment rack. One rack unit is equal to 1.75 inches (4.45 cm).

Radiated Emission
The potential EMI that emits from paths including cables, leaky apertures, or inadequately shielded housings.

Radiated Susceptibility
Undesirable EMI radiated into equipment from outside electromagnetic sources.

Radical copolymerization
A copolymerization which is a radical polymerization. (IUPAC)

Radio Frequency (RF)
The frequency range is technically broad, from about 25 kHz to 100 GHz, but the term is normally used to define the low range band of frequencies used for broadcast radio signals (including broadcast television) and extends from about 500 kHz to a few hundred megahertz.

Radio Frequency Contact (RF Contact)
An impedence matched shielded contact.

Radio Frequency Gluing System
Radio Frequency Gluing is a process in which high radio frequency waves are used to heat substrates, causing the adhesive between them to dry.

Radio Frequency Interference (RFI)
The disruption of signals which can be caused by high voltage and lightning.

Radio Frequency Over Glass (RFoG)
An SCTE 174 standard released in 2010, RFoG addresses PON network transmission for the CATV industry.

Radius
Half of the diameter of a circle measured from the center point.

Radius of curvature
Curvature of the endface measured from the side of the connector ferrule. Referenced in millimeters.

RAM
The moving portion in the head of a crimping tool. (MIL-STD)

Raman fiber amplifier
These amplifiers use the Raman effect to transfer power from pump lasers to the amplified wavelengths.

RAMP
The sloped channel that accepts the detent pin in a bayonet connector

Random copolymer
A copolymer consisting of macromolecules in which the probability of finding a given monomeric unit at any given site in the chain is independent of the nature of the adjacent units. Note in a random copolymer, the sequence distribution of monomeric units follows Bernoullian statistics. (IUPAC)

Random copolymerization
A copolymerization in which an alternating copolymer is formed. (IUPAC)

Random Width
Lumber ripped to no specific width. Used as edge glued stock. Defecting is done here as well as in specific width ripping.

Random Winding
A winding in rotating equipment wherein the wires do not lie in an even pattern .

Range
Number of sizes of connectors or cables of a particular type.

Range Wire
The sizes of conductors accommodated by a particular barrel. Also the diameters of wires accommodated by a sealing grommet. (MIL-STD)

Ratchet Control
A device to ensure the full crimping cycle of a crimping tool. (MIL-STD)

Rate of creep
The slope of the creep-time curve at a given time.

Rated Temperature
The maximum temperature at which an electric component can operate for extended periods without loss of its basic properties.

Rated Voltage
The maximum voltage at which an electrical component can be operated for extended periods without undue degradation or safety hazard.

Rayleigh Scattering
The scattering of light that results of from small in-homogeneity in material density or composition.

RBOC (Regional Bell Operating Company)
A holding company formed by the divestiture of AT&T to provide both regulated and non-regulated telephone services.

RC2000
See Radiocom 2000

Reactance
The opposition offered to the flow of alternating current by the inductance or capacitance of a component or circuit.

Reactance Drop
With AC, that component of the voltage drop which is in quadrature with the current and equals the current in amperes multiplied by the reactance in ohms between the two points.

Reactive Material
A chemical substance or material that will vigorously polymerize or decompose.

Reactivity
Tendency of a substance to undergo a chemical reaction with itself or another material with the release of energy.

Rear Mounted
A connector is rear mounted when it is insta1led from the inside of a box onto a panel. It can only be removed from the inside of the equipment. See Back Mounted.

Rear Release Contacts
Connector contacts are released and removed from the rear (wire side) of the connector. The removal tool engages the contact from the rear and pulls the contact out of the connector contact retainer.

Rear Seal
An elastomeric seal used on the cable side of a connector to seal the connector against moisture, dirt and air. (MIL-STD). Also called Grommet

Receive (Rx)
Refers to the detection of light from an optical source.

Receive cable
A known good fiber optic jumper cable attached to a power meter used as a reference cable for loss testing. This cable must be made of fiber and connectors of a matching type to the cables to be tested.

RECEIVER (Optical)
A device containing a photodiode and signal conditioning circuitry that converts light into an electrical signal in fiberoptic links.

Receiver (RCVR)
An electronic unit that converts an optical signal to an electrical signal using an APD or PIN photodiode.

Receiver sensitivity
This tells how much optical power the photodetector must receive to achieve a specified base band performance, such as a specified bit error rate or signal-to-noise ratio. Expressed in dBm.

Receptacle
A connector adapter with an internal LED, laser or detector that connects to optical plug assemblies.

Receptacle Connector
An electrical fitting with contacts constructed to be electrically connected to a cable, coaxial line, cord or wire to join with another electrical connector and is designed to be mounted on a bulkhead, wall, chassis or panel. (MIL-STD)

Reconfigurable OADM (ROADM)
Unlike OADMs, ROADMS can be managed via a network connection without need for a truck roll. They function as optical switches, allowing for remote service changes, and provide an express wavelength path and power monitoring.

Recovered Diameter
Diameter of shrinkable products after heating has caused it to return to its extruded diameter.

Recovered ID
In heat-shrink tubing the guaranteed maximum internal diameter of tubing after being freely recovered.

Red Plague
A powdery brown-red oxide of silver formed with water or rocket fuel fumes. It is highly conductive and can flake off and cause shorts in electrical equipment.

Redraw
The consecutive drawing of wire through a series of dies to reach a desired wire size.

Reduced viscosity/viscosity number
The ratio of the relative viscosity increment to the mass concentration of the polymer. (IUPAC)

Reducing Joint
A joint between two lengths of cable where the conductors are not the same size.

Redundancy Risers
A fail-safe method of splitting and routing riser/ backbone cables via two or more riser cores. Also known as diverse routing.

Reel
A revolvable flanged device made of wood or metal, used for winding flexible metal wire or cable.

Reel Drum Diameter
Diameter of the drum (or hub) of the reel.

Reel Traverse
Width of space between reel flanges.

Reel Width
Overall width of reel.

Reference cables
Cables used as a reference for testing a fiber optic assembly on either an optical loss test set (OLTS) or an optical return loss (ORL) test set. Usually nulled or zeroed out to measure the loss of a fiber optic assembly.

Reference Edge
The edge of a cable or conductor from which measurements are made.

Reference Junction
The junction of a thermocouple which is at a known reference temperature. Also known as the cold junction. It is usually located at the emf measuring device.

Reflectance
The percentage of light reflected from a component, such as a connector, splice, splitter, or WDM.

Reflection
The change in direction (or return) of waves striking a surface. For example, electromagnetic energy reflections can occur at an impedance mismatch in a transmission line, causing standing waves. See VSWR.

Reflection Coefficient
The ratio of the amplitude of the reflected wave to the amplitude of the incident wave in a transmission line.

Reflection crack
A crack through a bituminous overlay on Portland cement concrete pavement. The crack occurs above any working joint in the base pavement.

Reflection Loss
The part of a signal which is lost due to reflection of power at a line discontinuity.

Reflection Loss (Fiber Optic)
Energy reflected back toward a cable source. The reflections occur because the signal strikes a non-uniformity in the shield or conductor.

Reflow Oven
A reflow oven is a high-precision oven used primarily for soldering electronic components to printed circuit boards using surface mount techniques. The oven contains multiple zones, which can be individually controlled for temperature. Generally there are several heating zones followed by one or more cooling zones. The printed circuit board moves through the oven on a conveyor belt, and is therefore subjected to a controlled time-temperature profile. 

Reflow Soldering
The process of connecting two solder-coated conductive surfaces by remelting of the solder to cause fusion.

Refraction
The bending of a beam of light at an interface between two dissimilar media or in a medium whose refractive index is a continuous function of position (graded index medium).

Refractive index
The ratio of light velocity in a vacuum to its velocity in the transmitting medium. A property of optical materials that relates to the velocity of light in the material.

Regional Bell operating company (RBOC)
A company formed from the forced breakup of AT&T and the Bell system.

Register Ton
Old term for the measuring of ships, not to be used anymore. (One register ton is 100 cubic feet or 2.93 cubic metres).

Registration
Alignment of one object with relation to another. Also called Register.

Regular Lay Rope
Wire rope in which the wires in the strands and the strands in the rope are laid in opposite directions

Regular macromolecule
A macromolecule in which the constitutional units are all identical with respect to both constitution and orientation. (IUPAC)

Regular oligomer molecule
An oligomer molecule in which the constitutional units are all identical with respect to both constitution and orientation. (IUPAC)

Regular polymer
A substance composed of regular macromolecules. (IUPAC)

Reinforced Sheath
The outermost covering of a cable that has a cable sheath construction in layers with a reinforcing material, usually a braided or double spiral fiber, molded in place between layers.

Reinforcement
A material used to reinforce strengthen or give dimensional stability to another material. In sealants, this is the increase in modulus, toughness, tensile strength, by the addition of selected fillers; in pressure sensitive tapes, material added to a tape to provide additional strength.

Relative Intensity Noise (RIN)
Light is reflected back into a laser and amplified through the same physical mechanism that causes laser action. Caused by reflections from discontinuities in endfaces, connectors, or splices.

Relative Viscosity Increment
The ratio of the difference between the viscosities of solution and solvent to the viscosity of the solvent. (IUPAC)

Release agent
An adhesive material which prevents bond formation.

Release coat transfer
Condition in which particles of the release coat stick to the adhesive during the unwind phase -- result_ing tape will have little or no ability to stick.

Release coating
A coating applied to the backing on the side opposite the adhesive, which provides ease of unwind, and prevents delamination or tearing.

Release liner
A web or sheet of material covering the adhesive side of a tape. It is removed prior to appli_cation. Most frequently found on double-coated tapes and label stocks.

Release paper
A sheet, serving as a protectant and/or carrier for an adhesive film or mass, which is easily removed from the film or mass prior to use.

Remanence
The magnetic induction that remains in a magnetic circuit after the removal of an applied magnetomotive force.

Remote terminal (RT)
A POTS-related switching terminal that is remotely located in a pedestal or electronics cabinet.

Removable Contact
A contact that can be mechanically joined to or removed from an insert. Usually, special tools are required to lock the contact in place or to remove it for repair or replacement.

Removal Tool
A device used to remove removable contacts from a connector.

Repeatability
The amount of power lost due to the number of matings (de-matings) a connector experiences.

Repeater
Devices that receive a radio signal, amplify it and retransmit it in a new direction. Used in wireless networks to extend the range of base station signals, thereby expanding coverage within limits more economically than by building additional base stations. Repeaters typically are used for buildings, tunnels or difficult terrain.

Repeater, regenerator
A device that receives a fiber optic signal and regenerates it for retransmission, used in very long fiber optic links.

Reseller
In telephony, a middle-person who buys blocks of time from a cellular carrier at discounted wholesale rates and then resells them at retail prices.

Resilience
A measure of energy stored and recovered during a loading cycle. It is expressed as a percentage.

Resin
A synthetic organic material formed by the union (polymerization) of one or more monomers with one or more acids. Solid, semisolid, or liquid, usually organic material that has an indefinite molecular mass and, when solid, usually has a softening or melting range and exhibits a tendency to flow when subjected to stress.

Resinoid
Any of the class of thermosetting synthetic resins, either in their initial temporarily fusible state or in their final infusible state.

Resistance
1) Property of a conductor that determines the current produced by a given difference of potential.  2) A measure of the difficulty in moving electrical current through a medium when voltage is applied.  3) A measure of the difficulty in moving electrical current through a medium when voltage is applied. It is measured in ohms.

Resistive Conductor
A conductor with high electric resistance.

Resistivity
The ability of a material to resist passage of electrical current either through its bulk or on a surface.

Resistor
An electronic component that opposes the flow of electrical current. 

Resonance
An AC circuit condition in which inductive and capacitive reactances interact to cause a minimum or maximum circuit impedance.

Retractile Cable
A cable that returns by its own stored energy from an extended condition to its original contracted form.

Retractile Cord
A cord having specially treated insulation or jacket so that it will retract.

Retractile Cordset
Cable formed into the shape of a spring by winding cable around a mandrel and heat set into that shape (also referred to as coiled cord or cordset). this permits the extension of a cordset to a length from 3 to 5 times it's length at rest. A cordset will typically return, after being extended and released, to a length similar to it's original length at rest.

Retractile Springback
The rate of the coiled portion of a cordset, when released from being held in an extended position, to return to it's approximate original length. Springback, in simplest terms, can be specified as rapid, medium or controlled.

Return Loss
The Channel Return Loss (RL) is a measure of the consistency of the impedance down the length of not just the cable, but also the connections and the patch cables.

Return Wire
A ground wire or the negative wire in a direct-current circuit.

Reverse Bend
Reeving of a wire rope over sheaves and drums so that it bends in opposite directions

Reverse Strength
Strength represented by the inner wires of a wire rope

REVERSED PAIR
See also SPLIT PAIR and TRANSPOSED PAIR. A situation that occurs when the one end of a twisted pair has its connections reversed. This condition is detected by a LAN Cable Tester’s Wiremap test. (also see SPLIT PAIR and TRANSPOSED PAIR).

RF Connector
Connector used for connecting or terminating coaxial cable.

RF Fingerprinting
RF fingerprinting technology is based on the fact that no two handsets have the same signature. Once a call is places, the signature is compared to the RF fingerprint in the carrier’s database. The user’s mobile identification number and electronic serial number are then compared. If the MIN and ESN do not match the fingerprint, the call does not go through.

RGB Format
The television format that uses the basic component set of Red, Green and Blue.

Rheology
Special consideration of viscosity. Considers the effect of such things as stickiness and sensitivity to shear on viscosity.

RHH
Rubber-insulated, heat resistant building wire, 90°C, dry locations.

RHW
Rubber-insulated building wire, heat and moisture-resistant, 75°C wet or dry locations, now allowed to be cross-linked polyethylene insulated.

Ribbon Cable
Flat cable with conductors that have been individually insulated together and "glued together".

Ribbon Fiber Cable
A cable that accommodates 1 to 12 ribbons, each ribbon having 12 fibers for a cable size range of 12 to 216 fibers. Ribbon cables are designed for use in large distribution systems where small cable size and high pulling strength are important.

Ribbon Riser Cable
An optical fiber, nonconductive, riser (OFNR)-rated premises cable containing optical fibers in ribbons.

Ribbon splice
A fusion or mechanical splice that aligns and fuses or mechanically bonds two ribbon fibers together. Ribbon splices require special stripping and cleaving tools.

Ridge Marker
One or more ridges running laterally along the outer surface of a plastic insulated wire for purposes of identification.

Rigging
Any assembly made from wire rope that is to be used in a lifting, pulling, holding, or strapping capacity; Wire rope or aircraft cable used for securing the mast and/or boom on a sail boat, and for running of sails

Right Lay
1) Strand - Strand in which the cover wires are laid in a helix having a right-hand pitch, similar to a right-hand screw; 2) Rope - Rope in which the strands are laid in a helix having a right-hand pitch, similar to a right-hand screw

Rights of way (ROW)
Legal right of passage over land owned by another.

Rigid Bay
Cabling equipment that maintains component sequence, and can produce cables with distinct layers.

Rigid Cable
A cable (usually large in diameter) having a heavy metal outer conductor and a center conductor supported by dielectric beads. This cable cannot be bent, which will cause the conductors to be nonconcentric and sacrifice electrical performance. Used primarily for low frequencies and high power.

Rigid Coaxial Cable
Non-flexible coaxial cable, usually a metal tube armored coaxial cable.

Ring
A closed loop network topology.

Ring Banding
A circumferential color band applied to an insulated conductor at regular intervals for identification.

Ring In (RI)
Port for connecting multistation access units (MAUs) together.

Ring Out (RO)
Port for connecting multistation access units (MAUs) together.

Ring Tongue
A solderless terminal that connects wire to a stud.

Ring Tongue terminal
Round end tongue terminal with hole to accomodate screw or stud.

Ring topology
A communications topology in which each station is logically arrayed in a ring and passes information to the next station in order.

Ring-opening copolymerization
A copolymerization which is a ring-opening polymerization for at least one monomer. (IUPAC)

Ring-opening polymerization
A polymerization in which a cyclic monomer yields a monomeric unit which is acyclic or contains fewer cycles than the monomer. If the monomer is polycyclic, opening of one ring is sufficient to classify the reaction as ring-opening polymerization. (IUPAC)

Ringing Out
The process of locating or identifying specific conductive paths by means of passing current through selected conductors.

RIP
Routing Information Protocol

Rip Cord
1) Two or more insulated conductors in a parallel configuration which may be separated to leave the insulation of each conductor intact; 2) A small filament cord used to rip through the outer cable sheath.

Ripcord
An internal element placed under the cable jacket to assist the technician in stripping and removing cable jackets.

RIPE
Reseaux IP Europeens

RIPE NCC
Reseaux IP Europeens Network Coordination Centre

Ripple
The AC component of the output of a DC signal. This term typically refers to the residual line-frequency-related AC part in the output of a DC power supply that arises as a result of incomplete or inadequate filtering. The amount of filtering depends on the ripple frequency and the load resistance. More filtering is required as load resistance decreases.

RIR
Regional Internet Registry

RISC
Reduced Instruction Set Computer

Rise Time
The time required for a component or logic circuit to change from the quiescent to the transient state when an input is applied, (e.g. elapsed time between application of input and attainment of full output level).

Riser
Pathways for indoor cables that pass between floors. It is normally a vertical shaft or space. A riser cable rating indicates good flammability characteristics, but not necessarily low smoke as in a plenum type.

Riser Backbone Subsystem
The part of a premises distribution system that includes a main cable route and structure for supporting the cable from an equipment room (often in the building basement) to the upper floors, or along the same floor, where it is terminated on a cross connect in a riser telecommunications closet, at the network interface, or at distribution components of the Campus Backbone Subsystem. The Riser Backbone Subsystem usually extends from an equipment room (often in a building's basement) to the upper floors in a multistory building, or along the same floor in a low-wide building. It is terminated on a cross connect in a riser telecommunications closet, at the network interface, or on the distribution components of the Campus Backbone Subsystem.

Riser Cable
Cable installed in vertical runs and penetrating more than one floor or cables installed in vertical runs in a shaft. Rated by the NEC/CEC for resisting flame spread and smoke generation.

Riser(s)
The term used to describe a space utilized by backbone cabling to house communications cabling and other building services. This space should preferably be specified, or allowed for, at the time of the building design.

RL
Return Loss.

Rlin
Return loss of input connector

RLout
Return loss of output connector (if measured)

Roaming
Using a cellular phone outside one’s usual service area. For example, in a city other than where one lives.

Roll-off
An OTDR trace of a fiber that gradually rolls off due to nonreflective breaks.

Rollers
Relatively small diameter cylinders which are free to turn while supporting ropes

ROM
Read-Only Memory

Room-temperature-setting adhesive
An adhesive that sets in the temperature range from 20 to 30°C (68 to 86°F).

Root Mean Square (RMS)
The effective value of an alternating current or voltage.

Rope Concentric
A group of standard conductors assembled in a concentric manner.

Rope Lay Conductor
A conductor composed of a central core surrounded by one or more layers of helically laid groups of wires used in portable cables.

Rope Strand
A conductor composed of a center group of twisted strands surrounded by one or more layers of similar groups of twisted strands.

Rope Unilay
A group of stranded conductors assembled in a unilay manner.

Rosin
A resin obtained as a residue in the distillation of crude turpentine from the sap of the pine tree (gum resin) or from an extract of the stumps and other parts of the tree (wood rosin).

Round Conductor
A conductor whose cross-section is substantially circular.

Round Wire
A wire circular in cross section as opposed to flat, square, etc.

Round Wire Shields
Shields constructed from bare, tinned or silver plated copper wire that include braided, spiral, and reverse spiral.

Router
A device used to connect LAN’s utilizing different communications protocols. It directs traffic within networks and offers security by restricting access to those that don’t belong. Routers require intensive programming instructions and are used mostly for WAN (wide area network) interface to outside services.

Routing
The path followed by a cable or a conductor.

Rubber
A general term used to describe wire insulation and jackets made of thermosetting elastomers, such as natural or synthetic rubbers, EPR, neoprene, Hypalon, butyl rubber and others. An elastic (natural or synthetic) material (e.g. silicone) used to provide waterproofing or moisture resistance. See O-ring.

Rubber (Wire Insulation)
Wire insulations made of thermosetting Elastomer, natural or may be made synthetically.

Rulan
DuPont's trade name for their flame retardant polyethylene insulating material.

Rupture
In the breaking strength or tensile strength tests, the point at which the material physically comes apart, as opposed to elongation, yield strength, etc.

Rural Statistical Area (RSA)
The Federal Communications Commission divided the less-populated areas of the country into 428 RSAs and licensed two service providers per RSA.

S-band
The frequency spectrum from 2 GHz to 4 GHz used for land based microwave and some mobile satellite communications. The “short” DWDM transmission band, which occupies the 1460-1530 nm wavelength range.

S-MAC Serial Multiplexed Analog Component
A proposed standard for television transmission. The signal uses time compression and time domain multiplexing to transmit luminance and color difference signals as a single channel signal.

S/N (Signal to Noise Ratio)
The ratio of total signal to noise level, usually expressed in decibels.

Safe Working Voltage
Limit of continuous voltage for cable operation. Usually specified at 70% of Corona Extinction Voltage.

Safe-Tying
That feature of a connector design which permits safety wiring of plug and/or receptacle to prevent the loosening or vibrating free of the plug from the receptacle.

Safety Wire
A means of safety wiring a plug and/or receptacle to prevent the loosening or vibrating free of the plug from the receptacle.

Sag
The distance measured vertically from the fiber optic cable to the straight line joining two points of support. Unless otherwise stated, the sag referred to is at the mid-point of the span.

Sag section
A section of line between two dead-end structures. One or more of these sections may be present in a stringing section.

Sag span
A span selected within a sag section used as a control to determine the proper sag, and therefore tension of the fiber optic cable. At least two and normally three sag spans in a sag section, are required to sag a section properly. This may be increased where span lengths vary greatly and/or the terrain is hilly or mountainous.

Sag tension
The tension at which the fiber optic cable is designed to be installed. Usually at the initial sag.

Satellite Cabinet
Surface-mounted or flush-type wall cabinets for housing circuit administration hardware. Satellite cabinets, like satellite telecommunications closets, supplement riser telecommunications closets by providing additional facilities for connecting horizontal cables from information outlets in user work areas. Sometimes referred to as a "satellite location".

Satellite Telecommunications Closet
A walk-in or shallow wall closet that supplements a riser telecommunications closet by providing additional facilities for connecting riser backbone cables to horizontal cables from information outlets. Also referred to as a "satellite location". See also Riser Telecommunications Closet.

SC connector
Subscriber connector, a push/pull connector style that is recognized as the preferred optical fiber connector standard. It is available in simplex, duplex, hybrid, or hardened styles. The SC (Subscriber Carrier) fiber optic connector is one of three connectors (the other two are ST and SFF) approved by ANSI/TIA/EIA 568-B.3. The SC Connector’s main advantage is polarization since the connectors can be paired and keyed.

Scaleable
The ability to adapt to different bit rates.

Scattering
Property of glass that causes light to deflect from the fiber and contributes to optical attenuation. The change of direction of light after striking small particles that causes loss in optical fibers.

Scoop-Proof
Connectors with long shell design to insure proper alignment during mating, thus avoiding damaged pins or electrically shorted contacts. (MIL-STD)

Screen
A shield placed over the entire core.

Screened Cables
A cable core design where an aluminum shield divides the cable core into two electrically separate compartments.

Screening Effectiveness
Ratio of the power fed into a coaxial cable to the power transmitted by the cable through the outer conductor.

Screw Machine Contact
A contact made by screw-machine operations from bar or rod material.

Screwlock
A screw attached to one half of a two-piece multiple contact connector used to draw and hold both halves together and to separate them. (MIL-STD) Also called Jackscrew

Scribe
When an optical fiber is slightly scratched and then broken (scribing) to achieve a 90° endface. For splicing, the scribe tool needs to cleave as close as possible without angles, chips, or cracks. These tools are more expensive than hand scribe tools used for connectorization, where the final polish will be performed by machine or hand.

Scribe tool
See cleave tool.

Sealant
Solft, tacky, pliable material that seals where mechanical strength is not required.

Seale
A strand construction having one size of cover wires with the same number of one size of wires in the inner layer and each layer having the same length and direction of lay

Sealer
Surface coating generally applied to fill cracks, pores, or voids in a surface.

Sealing Plug
A plug that is inserted to fill an unoccupied contact aperture in a connector insert. Its function is to seal, especially in environmental connectors.

Seamless Terminal or Splice
Terminal or splice conductor barrel made without an open seam. (MIL-STD)

Secondary Insulation
A nonconductive material that protects the conductor against abrasion and provides a second electrical barrier. A high resistance dielectric material which is placed over primary insulation to protect it from abrasion.

Segment
A cable run. Its maximum length is determined by the topology. A 10BASE2 segment may be up to 605 feet long. A 10BASE-T segment may be up to 328 feet long.

Segmental Conductor
A stranded conductor consisting of three or more stranded conducting elements, each element having approximately the shape of the sector of circle, assembled to give a substantially circular cross-section.

Seize
To bind securely the end of a wire rope or strand with seizing wire or strand

Selective Plating
The application of plating material to a limited portion of a connector contact, especially those areas susceptible to wear.

Selenium Cure
Process used to cure neoprene and rubber jacketed wires and cables.

Self Align
Two mating parts designed so that they will engage in the proper relative position.

Self Alignment
The tendency of leads to center themselves on solder pads due to the surface tension of the liquid solder.

Self Extinguishing
The characteristic of a material whose flame is extinguished after the igniting flame is removed.

Self Normal Jack
A jack that provides a connection between the two rear connectors, except when interrupted by the insertion of a video patch plug into the front panel receptacle.

Self Terminating Jack
A jack that automatically provides a 75 ohm termination on the circuit that is connected to the rear connector, except when a plug is inserted into the receptacle on the front panel.

Self-Align
Design of two mating parts so that they will engage in the proper relative position.

Self-healing ring (SHR)
A system architecture consisting of two counter-rotating directions for communications between nodes. In normal use, the data traffic is sent in both directions. In the event of a broken fiber in one of the fiber loops, the data will reach the affected remote device via the other fiber ring. In this way, data traffic can still travel to all surviving sections of the ring, even if the path is via a longer fiber route.

Self-Supporting Aerial Cable
A cable consisting of one or more insulated conductors factory-assembled with a messenger which supports the assemblage and which may or may not form a part of the electrical circuit.

Self-Supporting Cable
Any assemblage of conductors which incorporates a steel rope or steel sheath for added tensile strength, thus enabling it to be suspended between widely spaced supports.

Self-vulcanizing
Pertaining to an adhesive that undergoes vulcanization without the application of heat.

Semi-Conducting Jacket
A jacket having a sufficiently low resistance so that its outer surface can be kept at substantially ground potential by a grounded conductor placed under the jacket.

Semi-Conducting Tape
A tape of such resistance that when applied between two elements of a cable, the adjacent surfaces of the two elements will maintain substantially the same potential. Such tapes are commonly used for conductor shielding and in conjunction with metallic shielding over the insulation.

Semi-Conduction Jacket
A jacket having a sufficiently low resistance so that its outer surface can be kept at substantially ground potential.

Semi-Flexible Cable
A cable consisting of a tin-filled braid outer conductor which will allow repeated flexure without damage. It will not hold a stable shape but is able to be hand bent.

Semi-Rigid
A cable containing a flexible inner-core and a relatively inflexible sheathing material, such as a metallic tube, but which can be bent for coiling or spooling and placing in a duct or cable run.

Semi-Rigid Cable
Cable containing a flexible inner core and a relatively inflexible sheathing.

Semi-Rigid PVC
A hard semi-flexible polyvinylchloride compound with low plasticizer content.

Semi-Solid
An insulation cross-section having a partially open space between the conductor and the insulation perimeter.

Semiconductor
A material that has a resistance characteristic between that of insulators and conductors. In wire industry terminology, a material possessing electrical conductivity that falls somewhere between that of conductors and insulators. Usually made by adding carbon particles to an insulator. Not the same as semiconductor materials such as silicon, germanium, etc. Used for making transistors and diodes.

Sensitization
A state of immune response in which further exposure elicits an immune or allergic response.

Separate-application adhesive
A term used to describe an adhesive consisting of two parts, one part being applied to one adherend and the other part to the other adherend and the two brought together to form a joint.

Separator
A layer of insulating material which is placed between a conductor and its dielectric, between a cable jacket and the components it covers, or between various components of a multiple-conductor cable.

Sequential markings
Metric or footage designations located at periodic locations on the outer jacket of cables.

SEQUOIA™ Long Life Diamond Film (ÅngströmLap ®)

Serial Communications
See Serial Data Transmission.

Serial Data Transmission
Data transmission between computer devices using only a single circuit path. Whole bytes of information (8 bits) are sent in sequential pattern. Compares with parallel transmission. Parallel transmission is often used internally within computing devices because of the higher processing speeds which are possible, but for long-distance telecommunication, serial transmission is more economic in terms of line plant.

Serial Digital Video Transmission
Transmission of a video signal by a series of discrete "on-off" or "high-low" pulses.

Serial Port(S)/Transmission
Normally a DB 9 pin connector located on the mother board of a PC. A technique in which each Bit of information is sent sequentially on a single channel.

Serial Transmission
The sending of multiple data bits down a single line in a stream.

Serializer/deserializer (SERDES)
A device used in high-speed communications that converts data between serial and parallel data streams. Used to combine and separate multiple video and/or data channels to and from a single channel data stream. See TDM.

Series Circuit
A circuit in which the components are arranged end-to-end to form a single path for current.

Series Resistance
Any sum of resistances installed in sequential order within one circuit.

Serrations
Deformation of the inside surface of a conductor barrel to provide better gripping of the conductor or on the outside of the connector body to provide better gripping of the connector. (MIL-STD)

Serve
A wrapping of wires or fibers around a central core.

Served Wire Armor (SWA)
Spiral wrap of soft galvanized steel wires applied to a cable to afford mechanical protection and increase the cable pulling tension characteristics.

Server
A network device which provides a service to other network devices. Services include file, printer, communications or gateway.

Service Entrance
See Campus Cable Entrance.

Service Life
A period of time during which a device is expected to perform satisfactorily. (MIL-STD)

Service Loop
(a) Allowing for “slack” in a splice tray, closure, or vault to accommodate future needs. (b) When a device is terminated to the wire in the communications outlet, a fair amount of “slack” should be left on the wire and wound in the box to accommodate future trimming when devices are changed out.

Service Rating
The maximum voltage or current which a connector is designed to carry continuously. (MIL-STD)

Serving
A wrapping applied over the core of a cable or over a wire. Servings may be in the form of filaments, fibers, yarn, tape, etc. Often referred to as a binder.

Serving area (SA)
An area defined by 32 optical network terminals (ONTs).

Serving Closet
See Satellite Telecommunications Closet

Session Layer
Layer 5 of the OSI model. Responsible for establishment and control of dialogues between users on different machines. Synchronization for reliable data transfer and token management to control use of the connection are services provided by this layer.

Set
To convert an adhesive into a fixed or hardened state by chemical or physical action, such as condensation, polymerization, oxidation, vulcanization, gelation, hydration, or evaporation of volatile constituents.

Set Time
The period of time required to attain handling strength.

Setting temperature
The temperature to which an adhesive or an assembly is subjected to set the adhesive. (See also curing temperature and drying temperature.)

Setting time
The period of time necessary for an adhesive in an assembly to set under specified conditions of temperature or pressure, or both.

Sexless Connection
An interconnecting device in which the mating parts are exactly alike at their mating surfaces. Also called "Hermaphroditic Connector".

SFF CONNECTOR
See SMALL FORM FACTOR CONNECTOR.

Shackle
A "U" shaped fitting with pin

Shared Logic
The simultaneous use of resources in a computer by several users.

Shear adhesion failure temperature (SAFT)
Refers to the upper temperature limit at which an adhesive is able to support a certain amount of weight. Polymer degradation, incorrect raw material ratios and incorrect blending can affect the SAFT results. This is not a measure of the bond between the adhesive and a substrate, but a measure of the internal strength of the adhesive itself. Generally, as the shear strength of an adhesive system in increased, tack and adhesive performance will decrease.

Shear strength
An adhesive joint, the maximum average stress when a force is applied parallel to the joint. (See bond strength.)

Shear, Lap
Test to measure resistance to shear stress by bonding the ends of flat bars in an overlapping position.

Shear, Static
Test to measure resistance to shear stress by bonding a pin within a collar or ring.

Sheath
The combination of a metallic shield and an extruded plastic jacket applied as the outermost covering on a cable. In the absence of a shield, the extruded jacket may be designated as a sheath. The material, usually an extruded plastic or elastomer, applied outermost to a wire or cable to provide mechanical and environmental protection. Very often referred to as a jacket. A common term for the collection of twisted pairs of multipair cables. The outer covering or jacket of a multiconductor cable.

Sheave
A sheave wheel, complete with arm or frame, should be suspended from structures to permit stringing of fiber optic cables. The sheaves must be lined with urethane or neoprene and have a diameter as required in specifications for each type of fiber optic cable being installed for normal vertical suspension points. For increased deflection angles, large diameter sheaves or multiple sheave assemblies are required.

Sheilded Pair
A pair of wires, twisted together and covered with a conductive material to provide any potentially induced noise a quick path to ground.

Shelf life
The period of time, usually beginning with the date of manufacture, during which a stored adhesive will remain effective or useful. Same as storage life.

Shell
The outside case of connector into which the insert and contacts are assembled.

Shell Electrical Connector
The outside case of a connector into which the dielectric material and contacts are assembled. (MIL-STD)

Shield
1) A conducting housing or screen that substantially reduces the effect of electric or magnetic fields on one side thereof, upon devices or circuits on the other side. Cable shields may be solid, braided, or taped (longitudinally or spirally). 2) In cables, a metallic layer placed around a conductor or group of conductors to prevent electrostatic or electromagnetic interference between the enclosed wires and external fields.

Shield (Electrostatic)
In cables, a metallic layer placed around a conductor or group of conductors to prevent electrostatic interference between the enclosed wires and external fields. Also see Insulation Shield.

Shield Adapter
An intermediate device that allows the termination of the cable shield to the connector shell.

Shield Coverage
The physical area of a cable that is covered by the shield ing material and is expressed in percent.

Shield Dual
A set of two shields in which one shield is adjacent to and surrounds another shield. Dual shields provide higher shield effectiveness over a broader range of frequencies. They typically consist of a foil shield, surrounded by either a spiral strand or braid shield.

Shield Effectiveness
The relative ability of a shield to screen out undesirable interference. Frequently confused with the term Shield Coverage.

Shield Electrical Connector
An item especially designed to be placed around that portion of a connector which contains facilities for attaching wires or cables. It is used for shielding against electrical interference or mechanical injury and usually has provisions for passage of the wire. (MIL-STD)

Shielded
Cable that is protected from electromagnetic and radio-frequency interference by a metal sheathing. The shield may be composed of braided strands of copper (or other metal). 

Shielded Cable
A cable or group of wires enclosed within a conductive shield to minimize the interference effects of internal or external circuits.

Shielded Contact
A contact which carries alternating current and is shielded from unwanted signals (RFI and EMI). Generally, these contacts are not impedance matched.

Shielded Line
A transmission line whose elements confine propagated radio waves to an essentially finite space inside a tabular conducting surface called the sheath preventing the line from radiating radio waves .

Shielded Room
A room made free from EMI by applying shielding to floor, walls and ceiling surfaces and by suppressing any interference entering through the power lines

Shielded Twisted Pair Cable (STP)
An electrically conducting cable comprising one or more elements each of which is individually shielded. There may be an overall shield in which case the cable is referred to as a shielded twisted pair cable with an overall shield.

Shielded-Type Cable
A cable in which the surface of the insulation is at ground potential.

Shielding
Strands or tapes of conductive material, which can be formed into a braid, or spiral wrap, or longitudinal cover, around insulated conductors or cable to reduce signal interference. Typical shielding materials are copper, tin or silver plated copper and aluminum.

Shielding Effectiveness
The relative capability of a shield to screen out undesirable electric and magnetic fields and plane waves. The measurement is the ratio of the signal received without the shield to the signal received inside the shield.

Shielding Electronic
A physical barrier, that is usually electrically conductive, that reduces the interaction of electric of magnetic fields upon devices , circuits, or portions of circuits.

Shielding Gasket
A material used to maintain shielding effectiveness across a seam or gap in an electronic enclosure. It may be made from a variety of materials including fabric-wrapped foam, wire mesh, stamped metal and elastomer compounds.

Shock (Mechanical)
1) An abrupt impact applied to a stationary object.  2) An abrupt or non-periodic change in position, characterized by suddenness, and by the development of substantial internal forces

Shock Test
A test to determine the ability of a cable to withstand a violent physical concussion such as might occur during handling or use.

Shore
A scale for comparing hardness. Higher shore values represent harder materials.

Short
An unintended connection between 2 or more parts. This failure indicates insufficient insulation between metal conductors which were not intended to be connected.

Short chain
A chain of low relative molecular mass. (IUPAC)

Short Circuit
A condition that exists when two conductors are connected ahead of where they normally should be in a circuit. This causes reduced resistance and sometimes the undesirable side effects.

Short Wavelength
A commonly used term for light in the 665, 790, and 850 nm ranges.

Short-chain branch
An oligomeric offshoot from a branched chain. (IUPAC)

Shorting Plug
A connector device designed to mate with a receptacle connector to perform protective, environmental and/or electrical shorting functions. Also called Dummy Connector Plug

Shrink Ratio
An expression of how much the inside diameter of shrink tubing will reduce in size when recovered. The inverse of the expansion ratio.

Shrink Temperature
That temperature which effects complete recovery of a shrinkable product from the expanded state.

Shrink Tubing
Tubing which has been extruded, cross-linked, and mechanically expanded which when reheated will return to its original diameter.

Shrinkage
Percentage weight loss under specified conditions.

Shrinkage Ratio
The ratio between the expanded diameter and recovered diameter of shrinkable products.

Shroud Insulation
The portion of a barrel similar to an insulation grip except that it is not compressed around the conductor insulation. (MIL-STD). Also called Insulation Support.

Shunt Wire
A conductor joining two parts of an electric circuit to divert part of the current.

SHV (Safe High Voltage)
Coaxial connector with bayonet coupling mechanism. Working voltage 5 kV DC.

SIDE GROUP
An atom or a group of atoms (in addition monomers) bonded to one of two double-bonded carbon atoms (Example: "Cl" in CH2=CHCl)

Side Wall Bearing Pressure (SWBP)
A term used in reference to the pressure on a cable which is being pulled around a curved surface under tension. If excessive, SWBP can damage cable components and reduce the life of the cable.

Signal
1) An electrical impulse of a predetermined voltage, current, polarity and pulse width. Used to convey information, either digital, analog, audio or video.  2) A current used to convey information, either digital, analog, audio or video.

Signal Cable
A cable designed to carry current of usually less than one ampere per conductor to operate signal circuit devices.

Signal Ground
A common point of reference for all other signals in a communications interface.

Signal To Noise Ratio (SNR)
The ratio of the signal magnitude to the noise magnitude and is usually expressed in dB. The higher the SNR of a system, the better is its performance.

Signal-to-noise ratio (SNR)
The ratio of the power of the signal versus the power of the background noise, usually measured in decibels. Describes the quality of an electronic transmission system.

Signaling System 7 (SS7)
An out-of-band signaling system that provides basic routing information, call setup and other cell termination functions. Signaling is removed from the voice channel and put on a separate data network.

Silica Glass (Fiber Optic)
Glass made mostly from silica (silicon dioxide, SiO2) used to make fibers.

Silicon Carbide Film (ÅngströmLap ®

Silicon detector
A semiconductor that used absorbed photon energy to stimulate carriers from one energy level to a higher one. The change in charge across the junction is monitored as a current in the external photodiode circuit. Silicon photodetectors are commonly used in multimode systems operating at 850 nm.

Silicone
1) A material made from silicone and oxygen. It can be in thermosetting elastomer or liquid form. The thermosetting elastomer form is noted for high heat resistance; 2) A thermosetting Elastomer with excellent heat-resistant. Polymeric materials in which the four recurring chemical groups contain silicon and oxygen atoms at links in the main chain.

Silicone adhesive
A pressure-sensitive adhesive capable of functioning effectively at extreme temperatures.

Silicone Treating
A silicone liquid treatment applied to insulated conductors to allow for easy jacket stripping.

Silicone®
General Electric trademark for a material made from silicone and oxygen. Can be in thermosetting elastomer or liquid form. The thermosetting elastomer form is noted for high heat resistance.

Silver (Ag)
A highly conductive metal with atomic number 47. When applied as terminal plating, it provides a hard-oxide soft-base finish that requires only moderate pressure for a metal-to-metal contact. Silver plating is normally used on metals that are relatively good conductors such as copper and brass.

Silver Satin
Flat, untwisted cable used typically as a telephone extension cord. It should never be used in a Local Area Network.

Simple/signalling network management protocol (SNMP)
Network management architecture initially designed for the Internet but easily applied or extended to any network type.

Simplex
Transmission in only one direction. Generally a communications system or device capable of transmission in one direction only.

Simplex cable
A tight buffered breakout cable with only one fiber. Single-longitudinal mode (SLM) laser A laser, usually distributed feedback (DFB) type, where the spectral width is the width at the 20 dB down points dividedby 6.07.

Simplex Cable (Fiber Optic)
A single fiber cable.

Simulation results have shown that 40 Gigabit Ethernet may be possible at 50 meters (164 ft) and 100 Gigabit Ethernet at 15 meters (49 ft).[citation needed] In 2007
researchers at Pennsylvania State University predicted that either 32 nm or 22 nm circuits would allow for 100 Gigabit Ethernet at 100 meters(328 ft).

Sine Wave
A wave that can be expressed as the sine of a linear function of time, or space or both.

SINGLE BOND
One covalent bond (one shared pair of electrons between two atoms), represented by "-" (Examples: C-C, C-O)

Single Mode Fiber
A fiber wave guide in which only one mode will propagate. The fiber has a very small core diameter of approximately 8mm. It permits signal transmission at extremely high bandwidths and is generally used with laser diodes.

Single MTJ Testing
Using one MTJ to launch light into DUT, other end of DUT at Detector.

Single-Ended
Unbalanced, such as grounding one side of a circuit or transmission line.

Single-Faced Tape
Fabric tape finished on one side with a rubber or synthetic compound.

Single-Fiber Cable
A plastic-coated fiber surrounded by an extruded layer of plastic encased in a synthetic strengthening material, and enclosed in a plastic sheath.

Single-strand chain
A chain that comprises units always joined to each other through one single atom on only one of the units. (IUPAC)

Singlemode
Optical fiber with a small core diameter in which only single mode is capable of propagation. 8.3 micron is the common standard core size.

Singlemode Propagation
A method of introducing a light pulse into a single light ray (mode) into an optical fiber. Singlemode is typically used for long-haul applications of 2 to 50 kilometers using relatively expensive laser light sources usually operating at a 1310 or 1550 nanometer wavelength.

Sintering
Fusion of a spirally applied tape wrap jacket by the use of high heat to a homogeneous continuum. Usually employed for fluorocarbon, non-extrudable materials.

Sinusoidal
Varying in proportion to the sine of angle or time function. Ordinary alternating current is sinusoidal.

Size (sizing)
Application of a material (sealer, size) to the surface of an adherend, prior to that of the adhesive, in order to reduce the absorbency of the adherend.

Sizing
Applying a material to a surface to fill pores.

Skeleton Braid
Widely separated braid of fiber copper, or steel, used to hold core together, for reinforcing jacket or for shielding.

Skew rays
Rays of light that do not propagate through the axis of the fiber.

Skim Tape
Filled tape coated on one or both sides with a thin film of uncured rubber or synthetic compound to produce a coating suitable for vulcanization.

Skin Effect
1) The phenomenon in which the depth of penetration of electric currents into a conductor decreases as the frequency increases.  2) The tendency of alternating current, as its frequency increases, to travel only on the surface of a conductor.

Sleeve
A braided, knifed, or woven tube used over wires or components as insulation tubing. Also called Sleeving.

Sleeves
Short lengths of rigid metal pipe, approximately 4 in. (10.1 cm) in diameter, located in riser telecommunications closet, that allows cables to pass from floor to floor when closets are vertically aligned. Sleeves also provide for easy pulling of cable.

Sleeving
A braided, extruded or woven tube.

Slings
Wire ropes made into forms, with or without fittings, for handling loads and so made as to permit the attachment of an operating rope

Slings, Braided
A very flexible sling composed of several individual wire ropes braided into a single sling

Slitting
The designation to separate insulated parallel wires.

Slots
Openings in the floor of riser telecommunications closets that allow cables to pass thorough from floor to floor when closets are vertically aligned. A slot accommodates more cables than an individual sleeve.

Slotted tongue
A slotted tongue for sliding onto the screw or stud so that neither screw nor unit needs removing. (MIL-STD)

SMA (Subminiature A)
50 ohm - subminiature coaxial connector with screw type coupling mechanism. Frequency range DC-18 GHz.

Small form factor (SFF)
A connector that offers higher density electronic equipment, enclosures, and distribution panels, lower connector costs, easier termination, and better optical performance.

Smoke Density Rating
Test methodologies of various organizations designed to simulate smoke density generated during flame and burning and the results of a material when tested under a specific methodology. Several tests are typically used: NBS Smoke Density per ASTM E662, OSU per FAR 25, NBS Smoke Density per ISO 5659, IF index per NFF 16 or Smoke Density per NFX 10. Smoke density is designing to evaluate the visibility for escape from a burning area.

SMPTE Recommended Practice
Advisory operating information issued by the SMPTE, as differentiated from a Standard.

Snap on
Used to describe the easy removal or assembly of one part to another. A connector containing socket (female) contacts into which a plug connector having male contacts is inserted.

Snell’s Law
The principle of the angle of incidence when light passes through materials with differing refractive indices.

Socket Connection
A connector containing socket contacts into which a plug connector having male contacts is inserted.

Socket Contact
A contact having an engagement end that will accept entry of a pin contact. (MIL-STD)

Socket Contact Sleeve
A sleeve that holds the contact spring in the correct position within the socket contact.

Sockets
For plug-in devices, for use on panel boards, printed circuit boards and microelectronic components. (MIL-STD)

Soft Conversion
The process of changing a measurement from inch-pound units to equivalent metric units within acceptable measurement tolerances without changing the physical configuration of the items.

Soft Cure, AL-32xx Series
ÅngströmLink® materials with a consistency approximating Jell-O (Shore 00 ~ 30). Used for bulk encapsulation where the low modulus provides stress relief from mismatches in thermal coefficients of expansion. Good adhesion to a variety of substrates and a range of refractive indices to couple the light between the two materials of the joint.

Softening point
The temperature at which an adhesive goes from a solid to a molten form, measured in Fahrenheit or Celsius.

Solder
A metal or metal alloy, usually having a low melting point, used to join other metals having higher melting points than the solder.

Solder Contact
A contact or terminal with a cup, hollow cylinder, eyelet or hood to accept a wire for a conventional soldered termination.

Solder Cup
A tubular end of a terminal in which a conductor is inserted prior to being soldered. It is also the hollow cylinder at the rear of a solder contact where a wire is inserted and soldered in place.

Solder Eye
A solder type contact provided with a hole at its end through which a wire can be inserted prior to being soldered. (MIL-STD)

Solder Pot
The end of a terminal or contact in which the conductor is inserted prior to being soldered. (MIL-STD) Also called Solder Cup

Solder Sleeve
A heat-shrinkable tubing device containing a predetermined amount of solder and flux used for environmental resistant solder connections and shield termination.

Solder Terminal
An electrical/mechanical connection device that is used to terminate a discrete wire or wire3s by soldering. (See also "Solder Terminal, Bifurcated," "Cup Solder Terminal", "Hock Solder Terminal", "Perforated (Pierced) Solder Terminal, and "Turret Solder Terminal")

Solder Terminal , Hook
A solder terminal with a curved feature around which one or more wires are wrapped prior to soldering.

Solder Terminal, Bifurcated
A solder terminal with a slot or slit opening through which one or more wires are placed prior to soldering.

Solder Terminal, Cup
A cylindrical solder terminal with a hollow opening into which one or more wirews are placed prior to soldering.

Solder Terminal, Hook
A solder terminal with a curved feature around which one or more wires are wrapped prior to soldering.

Solder Terminal, Turret
A round post-type stud (stand-off) solder terminal with a groove or grooves around which one or more wires are wrapped prior to soldering.

Solder Type Connector
A connector in which the contact between the conductor and the connector is made by a soldered joint.

Soldering
A process of joining metallic surfaces with solder without the melting of the base metals. Soldering is an economical, versatile and fast termination method. A soldered connection has metallic continuity and, therefore, excellent long term reliability.

Soldering Iron
Tool with an internal heating element used to heat surfaces being soldered to the point where the solder becomes molten. 

Soldering Sleeves
Shrinkable tubing with a solder preform used for high-test reliability soldering connections or shield grounding.

Solderless Connection
The joining of two metals by pressure means without the use of solder, braze or nay method requiring heat. (MIL-STD)

Solderless Contact
A contact with a back portion that is a hollow cylinder which allows it to accept a wire. After a bared wire is inserted, a crimping tool is applied to crimp the contact metal firmly against the wire. Usually called a crimp contact.

Solderless Wrap
A technique of connecting stripped solid wire to a terminal post containing a series of sharp edges by winding the wire around the terminal. (MIL-STD)

Solid Conductor
A conductor consisting of a single wire.

Solids content
The percentage by weight of the nonvolatile matter in an adhesive.

Solvent
Liquid in which another substance can be dissolved.

Solvent adhesive
An adhesive having a volatile organic liquid as a vehicle. Discussion—This term excludes water-based adhesives.

Solvent Resistance
The ability of a material to retain physical and electrical properties after being immersed in specific solvents.

Solvent-activated adhesive
A dry adhesive on an adherend that is rendered tacky just prior to use by application of a solvent.

Source
A light emitter, either an LED or laser diode, in a fiber optic link; a device that when properly driven will produce information carrying optical signals.

Source Coupling Loss
Loss of light intensity as light from source passes into fiber.

Source Routing
A bridge uses source routing when the route to be followed is carried within each frame by the source stations. The source station acquires and maintains information by a search process, allowing parallel bridges to exist and to share traffic between the same two rings.

SP-1
All rubber, parallel-jacketed, two-conductor light duty cord for pendant or portable use in damp locations. 300 V

SP-2
Same as SP-1, but heavier construction, with or without third conductor for grounding purposes. 300 V.

SP-3
Same as SP-2, but heavier construction for refrigerators or room air conditioners. 300 V.

Space
Denotes applications peculiar to spacecraft and systems designed for operation near or beyond the upper reaches of the earth's atmosphere. (MIL-STD). Another name for a binary "0" in data communications.

Spacing
Distance between the closest edges of two adjacent conductors.

Spade Tongue Terminal
Slotted tongue terminal designed to slip around a screw or stud without removing the nut. (MIL-STD

Span
1) In flat conductors, the distance between the reference edge of the first and the last conductor; 2) In round conductors, the distance between centers of the first and last conductors ; (3) In aerial cable, the distance between poles or support clamp

Spark Test
A test designed to locate pinholes in an insulated wire by application of an electrical potential across the material for a very short period of time while the wire is drawn through an electrode field.

Specialized Mobile Radio (SMR)
A private, mobile dispatch radio service that is usually used by businesses, such as taxi services.

Specific Gravity
The ratio of the weight of any volume of substance to a weight of an equal volume of some substance taken as a standard, usually water for liquids and hydrogen for gases.

Specific Heat
The quantity of heat needed to raise the temperature of a mass of material as compared with the same amount of water.

Specific Inductive Capacity (SIC)
1)The ratio of the capacitance using the material in question as the dielectric, to the capacitance resulting when the material is replaced by air.   2)That property of a dielectric which determines the electrostatic energy stored per unit volume for a unit potential gradient. The ratio of the capacitance using the material in question as the dielectric, to the capacitance resulting when the material is replaced by air. The dielectric constant is the most important design parameter for coaxial cables and determines dimensions, losses and propagation characteristics. Also called Dielectric Constant

Specification
A document prepared specifically to support acquisition which clearly and accurately describes essential technical requirements for purchased material.

Spectral Bandwidth
The difference between wavelengths at which the radiant intensity of illumination is half its peak intensity.

Spectral Response
The response of a detector (or a system) over different wavelengths.

Spectral width
A full width half maximum (FWHM) measurement of a LED or laser light source to determine its optical width.

Spectrum
Frequencies that exist in a continuous range and have a common characteristic. A spectrum may be inclusive of many spectrums (e.g., the electromagnetic radiation spectrum includes the light spectrum, radio spectrum, infrared spectrum, etc.).

Speed of Light
186,000 miles per second.

Speed of set test
A series of tests run to determine how fast a given glue can build strength under ideal conditions.

Speed, Cure
Time needed for an adhesive to reach full strength.

Spheres, SIOP (Fiber Optic Center)
ÅngströmSphere™ silica spheres are manufactured using our own proprietary technologies which allow the essential properties of amorphous silica to be combined with unique control of duplication, both in form and particle size.

Spiral Marking
A continuous spiral mark applied to a conductor for identification.

Spiral Shield
A metallic shield of fine stranded wires applied spirally rather than braided.

Spiral Stripe
A color coding stripe applied helically to the surface of an insulated wire or cable.

Spiral Wrap
The helical wrap of a tape or thread over a core.

SPIRITS
Services in the PSTN/IN Requesting Internet Services

Spiro Chain
a chain that comprises constitutional units, joined so as to form an uninterrupted sequence of rings through single common atoms between adjacent rings. (IUPAC)

Splice
An interconnection method for joining the ends of two optical fibers in a permanent or semi-permanent fashion. Maybe thermally fused or mechanically applied.

Splice (fusion or mechanical)
A device that provides for a connection between two fibers, typically intended to be permanent.

Splice Closure
A cable and fiber management product that environmentally protects and houses optical splices. Available as in-line or butt style, the closure is usually in a dome or clamshell configuration. Splice closures can also hold connectors and optical splitters. Telcordia GR-771 specifies mechanical requirements and environmental specifications and tests.

Splice organizer
A tray or other device used for the permanent storage of mechanical or fusion optical splices.

Splice panel
A rack or wall-mounted panel that allows cables to be organized and spliced. The panel holds splice trays, secures the cable, grounds any metallic members, and organizes and stores buffer tubes, fibers, and splices.

Splice protector
A device which is placed over the fusion splice to provide mechanical strength and protection to allow easy handling of the splice for organization in a splice tray or other storage. Two types are the heat shrink protector and the butterfly.

Splice tray
A protective tray that holds spliced fibers for slack and protection.

Splicing
Interweaving of two ends of ropes so as to make a continuous or endless length without appreciably increasing the diameter. Also making a loop or eye in the end of a rope by tucking the ends of the strands

SPLIT PAIR
A situation that occurs when a twisted pair is misconnected so that it becomes _ of two separate pairs. The noise immunity of the twists is lost and an impedance mismatch is created. This wiring error will not show up as an error on a Wiremap, but will be indicated by very high NEXT. (also see also REVERSED PAIR and TRANSPOSED PAIR).

Splitter
A fiber device that optically splits signals. The splitters used in a PON outside plant network are optical splitters that distribute optical signals from the OLT into the ONTs. Splitters used in FTTx installations are specified by the ITU G.671 standard as wavelength independent couplers (WIC), which provide the same attenuation regardless of wavelength or direction.

Splitting ratio
The distribution of power among the output fibers of a coupler.

Spool
A revolvable flanged device made of wood or metal, used for winding flexible metal wire or cable.

Spread
The quantity of adhesive per unit joint area. Single spread refers to application of adhesive to only one substrate of a joint. Double spread refers to application of adhesive to both substrates of a joint.

Spread Spectrum
Originally developed by the military because it offered secure communications, spread-spectrum radio transmissions essentially "spread" a radio signal over a very-wide frequency band in order to make it difficult to intercept and jam.

Spring Finger Action
Design of a contact as used in a printed circuit connector or a socket contact, permitting easy, stress-free spring action to provide contact pressure and/or retention.

SPT-1
Same as SP-1, except all-thermoplastic. 300V. With or without third conductor for grounding.

SPT-2
Same as SP-2, except all thermoplastic. 300V. With or without third conductor for grounding.

SPT-3
Same as SP-3, except all-thermoplastic. 300V. With or without third conductor for grounding.

Square
A face glued construction that is approximately squared in cross section that will be turned on a lathe.

Square Mil
The area of a square one mil by one mil.

Squeeze out
Adhesive pressed out at the bond line due to pressure applied on the substrates.

ST® Connector
Type of connector used on fiber optic cable utilizing a spring loaded twist and lock coupling similar to the BNC connectors used with coaxial cabling.

Stability
The ability of a material to remain unchanged.

Stability Factor
The difference between the percentage power factor at 80 volts/mil and at 40 volts/mil measured on wire immersed in water at 750C for a specified time.

Stabilizer
An adhesive additive which prevents or minimizes change in properties, e.g.., by adherend absorption, demulsification, or rapid chemical reaction.

STALPETH
A cable sheath consisting of a corrugated steel (ST) shield applied over a corrugated aluminum (AL) shield and an outer polyethylene (PETH) jacket.

Stamped Contacts
Contacts made by stamping and bending sheet metal rather than by the machining of metal stock. Also called Sheet Metal Contacts

Standard
A document that establishes engineering and technical requirements for items, equipment, processes, procedures, practices and methods that have been adopted as standard. Standards may also establish requirements for selection, application and design criteria for material.

Standardization Documents
Specifications, standards, handbooks, QPL's and such other engineering records, drawings, purchase descriptions, etc., as are or may be utilized for comparable purposes

Standby Time
The amount of time a fully-charged wireless phone can be left on before its battery runs down.

Standing Wave
The stationary pattern of waves produced by two waves of the same frequency traveling in opposite directions on the same transmission line. The existence of voltage and current maxima along a transmission line is a result of reflected energy from an impedance mismatch

Standing Wave Ratio
A measure of the mismatch between the load the line. It is equal to 1 when the line impedance is perfectly matched to the load. (In which case the maximum and minimum are the same, as current and voltage do not vary along the line). The perfect match would be a 1 to 1 ratio.

Standing Wave Ratio (SWR)
In a transmission line, waveguide, or analogous system, a figure of merit used to express the efficiency of the system in transmitting power.

Stapler Cleaver
Shaped similar to a stapler, its blade is made from a material sharp enough to nick the fiber optic and, by pressing down on a flexible tongue, cleaving the fiber optic. Most often used in a cleave and crimp style connector, and for acceptance testing.

Star
A physical point to point network topology. A topology for communications networks that involves transmission of data through a central location to other users.

Star coupler
An optical splitter in which many fibers have their signals mixed at a single optical element. The mixed signals are then transmitted back through all the fibers. The name comes from the geometrical arrangement; all fibers come together at a single point.

Star Macromolecule
A macromolecule containing a constitutional unit from which more than two chains (arms) emanate. A star macromolecule with n linear chains (arms) attached to the central unit is termed an n-star, e.g., five-star. (IUPAC)

Star Physical Topology
See Star

Star Polymer
A substance composed of star macromolecules. (IUPAC)

Star Quad
A cable element which comprises four insulated conductors twisted together. Two diametrically facing conductors from a transmission pair.

Star Topology
A topology in which each telecommunications outlet/connector is directly cabled to the distribution device.

Start Bit
In asynchronous communications, a start bit and stop bit delimits each character to indicate to the receiver the character’s location.

Static Charge
An electrical charge that is bound to an object. An unmoving electrical charge.

Static Condition
Used to denote the environmental conditions of an installed cable rather than the conditions existing during cable installation.

Static Conductor
A conductor composed of single solid wires twisted together, either singly or in groups.

Static Noise
Signal distortion due to the electrical field radiated by a voltage source which has coupled into the signal-bearing circuit.

Static Shear
Test to measure resistance to shear stress by bonding a pin within a collar or ring.

Station Wire
PVC jacketed wire specially designed for use in ducts or stapled to surfaces for direct connection to subscriber's phone.

Statistical copolymer
A copolymer consisting of macromolecules in which the sequential distribution of the monomeric units obeys known statistical laws. An example for a statistical copolymer is one consisting of macromolecules in which the sequential distribution of monomeric units follows Markovian statistics. (IUPAC)

Statistical copolymerization
A copolymerization in which a statistical copolymer is formed. (IUPAC)

Statmux
Statistical Multiplexing

Stay Cord
A component of a cable used to anchor the cable ends at their points of termination and to keep any pull of the cable f rom being transferred to the electrical connections.

Steady state modal distribution
Equilibrium modal distribution (EMD) in multimode fiber, achieved some distance from the source, where the relative power in the modes becomes stable with increasing distance.

Steel
A material usually specified for applications requiring unusually high mechanical strength. Steel is used as a base metal and protected by a suitable plating.

Step Index Fiber (Fiber Optic)
A multimode fiber consisting of a core of uniform refractive index surrounded by cladding of a slightly lower refractive index. Accepts light rays over wider angle, but has smaller bandwidth than single mode fiber. See also Graded Index Fiber and Single Mode Fiber.

STEP-GROWTH POLYMERIZATION
Another name for condensation polymerization

Step-index fiber
A type of fiber where the refractive index of the core is uniformly higher than that of the surrounding cladding.

Stereoblock macromolecule
A block macromolecule composed of stereoregular, and possibly in addition non-stereoregular, blocks. (IUPAC)

Stereoblock polymer
A substance composed of stereoblock macromolecules. (IUPAC)

Stereoregular macromolecule
A regular macromolecule comprising only one species of stereorepeating unit. (IUPAC)

Stereoregular polymer
A substance composed of stereoregular macromolecules. (IUPAC)

Stereorepeating unit
A configurational repeating unit having defined configuration at all sites of stereoisomerism in the main chain of a regular macromolecule (or oligomer molecule or block). (IUPAC)

STOP BIT
The trailing bit in an asynchronous character sequence.

Stop Plate
A device attached to a crimping tool to properly locate a terminal, splice or contact in the tool prior to crimping. See locator. (MIL-STD)

Storage Area Network (SAN)
A high speed network or subnetwork of shared storage devices.

Storage life
The period of time during which a packaged adhesive can be stored under specified temperature conditions and remain suitable for use.

Straight Blade
Refers to a NEMA device with straight prongs.

Straight Connector
A connector which joins two lengths of conductor end-to-end in a straight line.

Straight-Tip (ST) Connector
A fiber optic connector used to join single fibers together at interconnects or to connect them to fiber optic cross connects.

Strain Damage
The disconnection of conductors from their termination points due to excessive axial stress.

Strain Gauge
A device for determining the amount of strain (change in dimensions) when a stress is applied.

Strain Relief
A technique involving devices or methods of termination or installation which reduce mechanical stresses from being transmitted to the conductor termination.

Strain Relief Clamp
A mechanical clamp attached to the cable side of the connector to support the cable or wire bundle, provide strain relief and absorb vibration and shock otherwise transmitted by the cable to the contact/wire connection. (MIL-STD) Also called Cable Clamp

Strand
(1) A single uninsulated wire; (2) One of the wires of any stranded conductor.

Strand Conductor Shield
A layer of semiconducting material or tape applied directly over the stranded conductor of cables rated 2,000 volts and higher. This reduces the possibility of high stress points occurring between the conductor and insulation.

Strand Lay
A distance of advance of one strand of a spirally stranded conductor, in one turn, measured axially.

Stranded Cable
A strong woven-copper-wire cable used to support cable in aerial distribution systems. The cable is lashed to the stranded cable during installation.

Stranded Conductor
A wire or cable constructed of several small strands of conductor instead of one larger solid piece. This configuration provides for more flexibility in certain applications. Patch cords are made out of stranded conductors and the NEXT values are degraded up to 20% to allow for them in a link.

Strap
Square- or rectangular-section bare conductor manufactured and used in coil form.

Strength Member
Part of a fiber optic cable composed of aramid yarn, steel strands, or fiberglass filaments that increase the tensile strength of the cable.

Strength, Hot
Strength measured at elevated temperature.

Strength, Impact
Resistance to sharp, intense blows or force.

Stringiness
The property of an adhesive that results in the formation of filaments or threads when adhesive transfer surfaces are separated. (See also legging and webbing.) (Compare teeth.) Discussion—Transfer surfaces may be rolls, picker plates, stencils, etc.

Strip
To remove insulation from a conductor. (MIL-STD)

Strip Force
The force required to remove a small section of insulating material from the conductor it covers.

Stripline
A type of transmission line configuration which consists of a single narrow conductor parallel and equidistant to two parallel ground planes.

Stripper
Mechanical tool used to remove buffer coatings from fibers.

Stripping
The designation of the removal of the insulation or jacket from a conductor/wire.

Structural Adhesive
A bonding agent used for transferring required loads between substrates exposed to service environments typical for the structure involved.

Structural Return Loss
Backward reflected energies from uneven parts of the cable structure causing impedance variations are termed structural return loss.

Structured Cabling
Flexible cabling scheme which allows rapid reconfiguration for office moves through patching.

Stud Cable
A short cable (usually 25 ft [7.6 m] or less) that extends from a cable terminal, protector, or block and is used to make connections to such devices.

Subminiature type A (SMA) connector
A nonkeyed, noncontacting, multimode threaded connector borrowed from the coax industry. Types include 905, 906, or optimate.

Subscriber Identify Module
The "SIM card" is an integrated-circuit chip housed in a plastic card which enables a cellular subscriber to use any (usually Global System for Mobile Communications) handset. The card identifies and bills the caller, no matter whose phone is being used.

Subscriber line interface circuit (SLIC)
The line card that provides the interface between local loop and telco switching equipment.

Substrate
A material upon the surface of which an adhesive-containing substance is spread for any purpose, such as bonding or coating. A broader term than adhered.

Substrate Failure
Condition of bond failure in which the substrate falls apart. The cohesive strength of the adhesive and the adhesive forces between the adhesive and substrate exceed the internal strength of the material being bonded.

Suggested Working Voltage
AC voltage that can be applied between adjacent conductors.

Super physical contact (SPC)
The spherical endface polish of a ferrule and fiber that is performed on a polishing machine. Typically 50 dB return loss. Superseded by the UPC polish.

Support Hardware
The racks, clamps, cabinets, brackets, trays, tools, and other equipment that provide the physical means to attach the transmission media and connecting hardware to walls or ceilings.

Surface Emitter LED
A LED that emits light perpendicular to the semiconductor chip. Most LEDs used in datacommunications are surface emitters.

Surface Mount Device (SMD)
An active or passive device designed to be soldered to the surface of the printed circuit board.

Surface Mount Technology (SMT)
The process of assembling printed circuit boards with components soldered to the surface rather than to plated through-holes.

Surface Mounting
The electrical connection of components to the surface of a conductive pattern without utilizing component holes in a circuit board.

Surface Primer
A surface primer is a coating that changes the character of a surface so that an adhesive or coating will adhere to it more effectively.

Surface Resistivity
The resistance of a material between two opposite sides of a unit square of its surface. It is usually expressed in ohms.

Surface-emitting LED (SLED)
A diode that emits light perpendicular to the semiconductor chip. Most LEDs used in data communications are surface emitting.

Surge
A temporary large increase in the voltage or current in an electric circuit or cable.

Surlyn
DuPont's trade name for their thermoplastic resin with ionic crosslinks.

Suspended Ceiling
A ceiling that creates an area or space between the ceiling material and the structure above the material. Synonym: Drop Ceiling, Suspended Ceiling.

SW1
Switch connected to output J1.

SW2
Switch connected to J2 or to Detector.

Sweep Test
A method to determine the frequency response of a cable by generating an RF voltage whose frequencies varied at a rapid constant rate over a given range.

Switch
A device for re-routing signals from one optical fiber into others. Types include MEMs, matrix, bypass, optical cross connect, and electrical network switches.

Switchboard Cable
A cable used within and between the central office main frames and the switchboard.

Switched multimegabit data service (SMDS)
A high-speed public packet switched data service that provides up to 155 Mb/s connectivity for LANs.

Switched video on demand (SVOD)
Television service provided over an established network but not continuously broadcast, therefore requiring less bandwidth than conventional broadcast systems. Signal transmission is initiated when a subscriber selects a channel, which triggers a request back to the service provider.

Switching
A function carried out by a switching hub, alleviating traffic by making virtual connections between transmitting and receiving nodes.

Swivel
Installation hardware used to eliminate winding and tangling of cables during installations.

Sync
A mixed signal consisting of Composite Sync, Color Burst and Video.

Sync Burst
A signal consisting of Composite Sync and Color Burst.

Synchronization
The method by which the bit patterns appearing on digital line systems may be properly "clocked" and interpreted�allowing the beginning of particular patterns and frame formats to be correctly identified.

Synchronous
Signals that are sourced from the same timing reference and hence are identical in frequency.

Synchronous Data Transfer
Data transfer employing a strictly regular pattern, rather than using start and stop bits to distinguish character patterns from idle line operation.

Synchronous digital hierarchy (SDH)
A worldwide, high-speed synchronous protocol standard transmitting at up to 10 Gb/s. Known as SONET in North America.

Synchronous optical network (SONET)
ANSI-standard physical interface defined by its optical line rates known as optical carrier (OC) signals, frame format and OAM&P protocol. Adopted by the ITU as SDH.

Synchronous transfer mode (STM)
A transport and switching method that depends on information occurring in regular and fixed patterns with respect to a reference such as a frame pattern.

Synchronous transmission
A transmission method in which data characters are synchronized by timing signals generated at sending and receiving stations (as opposed to start/stop communications). Both stations operate continuously at the same frequency and are maintained in a desired phase relationship. Several codes may be used as long as they utilize the required line control characters. Also called �bi-sync� or �binary synchronous.�

Synchronous transport signaling (STS)
The transmission speed of a SONET transmission medium, e.g., OC-48.

SyncML
Synchronous Markup Language

Syndiotactic macromolecule
A macromolecule comprising alternating enantiomeric configurational base units. Note in a syndiotactic macromolecule, the configurational repeating unit consists of two configurational base units that are enantiomeric. (IUPAC)

Syndiotactic polymer
A substance composed of syndiotactic macromolecules. (IUPAC)

System-Common Equipment
The equipment on a premises that provides functions common to terminal devices such as telephones, data terminals, integrated workstations terminals, and personal computers. Typically, the system-common equipment is the private branch exchange (PBX) switch, data packet switch, or central host computer. Often called common equipment.

T Connection
A connector fanning out in three directions and looking like a "T". Commonly used is a BNC T connector for 10BASE2 applications.

T-Carrier (AT&T)
A hierarchy of digital systems designed to carry speech and other signals in digital form, designated T1, T2, and T4. T1 carrier has 24 PCM voice channels.

Tack
The property of an adhesive that enables it to form a bond of measurable strength immediately after adhesive and substrate are brought into contact under low pressure. Same as aggressive tack.

Tack range
The period of time in which an adhesive will remain in the tacky-dry condition after application to a substrate, under specified conditions of temperature and humidity.

Tackiness
The stickiness of the surface of a sealant or adhesive.

Tacky-dry
Pertaining to the condition of an adhesive when the volatile constituents have evaporated or been absorbed sufficiently to leave it in a desired tacky state.

Tactic macromolecule
A regular macromolecule in which the configurational (repeating) units are all identical. (IUPAC)

Tactic polymer
A substance composed of tactic macromolecules. (IUPAC)

Tacticity
the orderliness of the succession of configurational repeating units in the main chain of a regular macromolecule (or oligomer or block). (IUPAC)

Tag Line
A small wire rope used to prevent rotation of a load

Take Rate
Subscribers divided by homes connected. Expressed as a percentage, it can also be based on each type of service, i.e., take rates for data, video, voice, or triple/quadruple services.

Take-Up
The process of accumulating wire or cable onto a reel, bobbin, or some other type of pack. Also, the device for pulling wire or cable through a piece of equipment or machine.

Talkset, fiber optic
A communication device that allows conversation over unused fibers.

Tank Test
A voltage dielectric test in which the test sample is submerged in water and voltage is applied between the conductor and water as ground .

Tannic acid
A compound that is most commonly found in oak, cherry, cypress and redwood trees.

Tap
An electrical connection to a bus to enable access. A tap may be invasive (requiring a cable splice), or non-invasive (a "vampire" tap).

Tape
A relatively narrow woven or cut strip of fabric, paper, or film material.

Tape Wrap
A spirally applied tape over an insulated or uninsulated wire.

Taped Insulation
Insulation of helically wound tapes applied over a conductor or over an assembled group of insulated conductors.

Taper Pin
A pin type contact having a tapered end designed to be impacted into a taper hole.

Tapering & Welding
Reducing the diameter of the end of a wire rope and welding it to facilitate reeving

Taping
Process of insulating continuous length, large diameter wires with tape of non-extrudable materials.

Tarnish
A term used to describe a discolored or stained conductor or shield wire caused by exposure to the atmosphere .

Tear Strength
The force required to initiate or continue a tear in a material under specified conditions.

Technical Horsepower Consulting, LLC
Wayne Kachmar's consulting company for optical cable technical expertise.

Tee coupler
A fiber optic coupler in which three fiber ends are joined together, and a signal transmitted from one fiber is split between the other two.

Teeth
The resultant surface irregularities or projections formed by the breaking of filaments or strings which may form when adhesive-bonded substrates are separated.

Teflon®
DuPont trademark for fluorocarbon resins.

Teflon�
DuPont trademark for fluorocarbon resins.

Tefzel®
DuPont Company trademark for high radiation resistant fluorocarbon (ETFE).

Tefzel�
DuPont Company trademark for high radiation resistant fluorocarbon (ETFE).

Telco
Telephone company, such as a BOC, RBOC, LEC, or PTT

Telcordia Technologies (Bellcore)
Formerly known as Telcordia-Bell Communications Research, it is the unofficial standards development body providing technical specifications for the RBOCs.

Telecommunications
Any transmission, emission, and reception of signs, signals, writings, images and sounds, that is information of any nature by cable, radio, optical or other electromagnetic systems.

Telecommunications Closet
A room where cables are terminated on cross-connect fields, where circuit administration takes place. There are two kinds of telecommunications closets: riser telecommunications closets and satellite telecommunications closets. See also Riser Telecommunications Closet and Satellite Telecommunications Closet. An enclosed space for housing telecommunications equipment, cable terminations, and cross-connect cabling. The telecommunications closet is a recognized cross-connect point between the backbone and horizontal cabling subsystems.

Telecommunications Grounding Busbar
A common point of connection for telecommunications system and bonding to ground, which is located in the telecommunications closet or equipment room.

Telecommunications Industry Association (TIA)
The US-based organization established to provide industry-wide standards for telecommunications equipment used in North America.

Telecommunications Infrastructure
A collection of those telecommunications components excluding equipment, that together provide the basic support for the distribution of all information within a building or campus.

Telecommunications outlet (TO)
A single-piece cable termination assembly (typically on the floor or in the wall) that contains one or more modular telecom jacks, e.g., RJs, coaxial terminators, fiber optic connections. If more than one type of connector is used, it is called a multiuser telecommunications outlet assembly (MUTOA).

Telecommunications space
The area used to house, install, and terminate telecommunications equipment and cable; e.g., telecommunications closets, work areas, and handholes.

Telegraphing
A condition in a laminate or other type of composite construction in which irregularities, imperfections, or patterns of an inner layer are visibly transmitted to the surface.

Telemetry Cable
Cable used for transmission of information from instruments to the peripheral recording equipment.

Telepoint
A cordless-telephone system is which a subscriber can make but not receive phone calls in public areas which have been equipped with Telepoint base stations. If the system is not mobile; the user must remain essentially in a fixed location throughout the duration of the call. Service and equipment are less expensive than cellular.

Telex
Teletypewriter Exchange Service

Telnet
Teletype Network

Telomer
a substance composed of macromolecules or oligomer molecules having few, usually terminal, reactive functional groups enabling, under appropriate conditions, the formation of larger macromolecules. (IUPAC)

Telomerizaton
a polymerization in which a telomer is formed. (IUPAC)

TEM Cell
Transverse electromagnetic cell; a chamber that maintains its characteristic impedance throughout its volume. Cable, connector assemblies, and electronic devices are placed inside the cell. The cell also can be used as a detector to measure radiation emitted by devices inside the cell.

Temper
1) The hardness and strength produced by mechanical or thermal treatment or both. It is characterized by a certain structure, mechanical properties or reduction in area during cold working. 2) A measurement of the degree of hardness or lack of ductility in a metal.

Temperature Coefficient of Resistivity
The amount of resistance change of a material per degree of temperature rise.

Temperature Rating
The maximum temperature at which the insulating material may be used in continuous operation with a loss of 50% of its original properties.

Temperature Rise
Temperature change of contact from a no-load condition to full current load. Also referred to as "T" rise.

Temperature Stress
The maximum stress which can be applied to a material at a given temperature without physical deformation.

Temperature, curing
The temperature to which an adhesive or an assembly is subjected to cure the adhesive.

Temperature, maturing
The temperature, as a function of time and bonding condition, that produces desired characteristics in bonded components.

Temperature, setting
The temperature to which an adhesive or an assembly is subjected to set the adhesive.

Tempest
A complex measurement of the combined reduction of all electromagnetic emissions from specified equipment used in high data security areas.

Tensile Strength
1) Greatest longitudinal stress that a substance can bear.��2) The pull stress required to break a given specimen.��3) The breaking strength per square inch of cross-sectional area of the material tested.

Tensile Stress
Force per unit cross sectional area applied to elongate a material.

Tensile Testing
A controlled pull test on the crimp joint to determine its mechanical strength.

Tensile-Flex
Trademark for Phelps Dodge� Alloy. 135 high strength copper alloy.

Tension Member
A member included in a fiber cable to add tensile strength.

Terminal
(1) A point at which information may enter or leave a communications network; (2) The input-output associated equipment; (3) A device by means of which wires may be connected to each other.

Terminal Block
A protected or unprotected unit of wiring blocks, connecting blocks, and troughs that serves as a transition point between cable conductors.

Terminal Server
A device that allows connection of several terminals and multiplexes them onto a LAN cable.

Terminals
Metal wire termination devices designed to handle one or more conductors, and to be attached to a board bus or block with mechanical fasteners or clipped on.

Terminate
To connect a wire or wires to a device or a matching impedance connection.

Terminating Cable
A multi-paired cable usually with tinned conductors and always with fire resistant insulation that is used primarily between the cable vault and the main distributing frame.

Termination
Preparation of the end of a fiber to allow connection to another fiber or an active device, sometimes also called "connectorization".

Termination tools
Tools used in preparing optical fibers for splicing and/or installation of connectors.

Terminator
An optical plug with the fiber dead ended so that there is no reflectance. Terminators measure component reflectance using the OTDR and also reduce Fresnel reflections at open connector ports.

Terrestrial Communications
A system where all transmitters and receivers are on the ground.

Test cable
A short single fiber jumper cable with connectors on both ends used for testing. This cable must be made of fiber and connectors of a matching type to the cables to be tested.

Test kit
A kit of fiber optic instruments, typically including a power meter, source and test accessories used for measuring loss and power.

Test Lead
A flexible, insulated lead wire used for making tests, connecting instruments to a circuit temporarily or for making temporary electrical connections.

Test source
A laser diode or LED used to inject an optical signal into fiber for testing loss of the fiber or other components.

Testing
The electrical test of an assembly to verify all expected connections; and to verify insulation prevents unexpected connections.

Tetrafluoroethylene (TFE)
A thermoplastic material with good electrical insulation properties and chemical and heat resistance. See also PTFE.

Textile Braid
Any braid made from threads of cotton, silk or synthetic fibers.

The following final polish films use silicon dioxide material and will polish the ceramic ferrule and glass fiber near the same rate. These films require only distilled water
and do not need messy slurries to meet back-reflection of -55dB or better for UPC

Themolabel
A pressure sensitive temperature measuring device that can be placed on a panel prior to pressing to measure maximum press or panel temperature.

Thermal Aging
Exposure to a thermal condition or programmed series of conditions for predescribed periods of time.

Thermal Rating
The temperature range in which a material will perform its function without undue degradation.

Thermal Resistance
That change in the electrical resistance of a material when subjected to heat. Resistance to heat flow from conductors to outer surface of insulation or sheath in a wire of cable.

Thermal Resistivity
Thermal resistance of a unit cube of material.

Thermal Shock
1) The effect of heat or cold applied at such a rate that non-uniform thermal expansion or contraction occurs within a given material or combination of materials.��2) A test to determine the ability of a material to withstand heat and cold by subjecting it to rapid and wide changes in temperature.

Thermocouple
A device consisting of two dissimilar metals in physical contact, which when heated will develop an emf output.

Thermocouple Contact
Contact made of special material used in connectors employed in thermocouple applications. Materials often used are iron, constantan, copper, chromel and alumel.

Thermocouple Element
A thermocouple designed to be used as part of an assembly, but without associated parts such as the terminal block, connecting head, or protecting tube.

Thermocouple Extension Cable
A cable comprised of one or more twisted thermocouple extension wires under a common sheath.

Thermocouple Extension Wire
A pair of wires of dissimilar alloys having such emf temperature characteristics complementing the thermocouple which is intended to be used, such that when properly connected, allows the emf to be faithfully transmitted to the reference junction.

Thermocouple Lead Wire
An insulated pair of wires used from the couple to a junction box.

Thermocouple Wire
A two conductor cable, each conductor employing a dissimilar metal, made up especially for temperature measurements.

Thermoelectric cooler (TEC)
A device used in laser transmitters to maintain a cool, stable temperature for a laser diode prolonging its life, maintaining stable output power, and promoting wavelength stability.

Thermoplastic
Polymer or copolymer capable of being softened by heating and hardened by cooling.

Thermoplastic Insulation
Jacket compounds (such as PVC, PE, and TPE) that will resoften and distort from their formed shapes by heating above a critical temperature peculiar to the material.

Thermoplastic, (adjective)
Capable of being repeatedly softened by heat and hardened by cooling.

Thermoplastic, (noun)
A material that will repeatedly soften when heated and harden when cooled.

Thermoset
A material which hardens or sets by heat, chemical or radiation cross-linking techniques and which, once set, cannot be re-softened by heating. A material that will undergo or has undergone a chemical reaction by the action of heat, catalysts, ultraviolet light, etc., leading to a relatively infusible state. Monomer, polymer or copolymer, which when cured, changes into a substantially infusible and insoluble product. A network polymer obtained by cross-linking a linear polymer to make it infusible or insoluble.

Thermoset, state of
Pertaining to the state of a resin in which it is relatively infusible.

Thermosetting
Having the property of undergoing a chemical reaction by the action of heat, catalysts, ultraviolet light, etc., leading to a relatively infusible state.

Theta State
The state of a polymer solution for which the second virial coefficient is zero. (IUPAC)

Theta Temperature
The temperature at which a solution is in the theta state. (IUPAC)

THHN
Thermoplastic insulated, high heat resistant, nylon jacketed cable, 90�C dry location, 75�C wet location.

Thick Coax
The transmission medium used for Ethernet or IEEE 802.3 10Base5 LANs. It is a 50 ohm thick coax cable (commonly referred to as the thick yellow cable).

Thickness
Distance from one surface of either a tape, backing or adhesive to the other, usually expressed in mils or thousandths of an inch; usually measured under slight pressure with a special gauge or caliper.

Thicknet
Another term for IEEE 802.3 10BASE-5 systems.

Thin Coax
The transmission medium used for IEEE 802.3 10Base2 LANs (sometimes referred to as CheaperNet). It is a 50 ohm thin coax cable.

Thin Ethernet
Normally describes a 10BASE-2 system. Also called Cheapernet.

Thinner
A volatile liquid added to an adhesive to modify the consistency or other properties.

Thixotropic
Nonsagging. A material that maintains its shape unless agitated. A thixotropic sealant can be placed in a joint in a vertical wall and will maintain its shape without sagging during the curing process.

Thixotropy
Term which describes the flow character of a liquid or paste. Liquids that are thixotropic flow under shear but flow less when the shear is removed. Best example is ketchup.

Thixotropy (non-sagging)
A material that maintains shape unless agitated. A thixotropic sealant can be placed in a joint in a vertical wall and will maintain its shape or position without sagging during the curing process.

Thread Coupling
A means of coupling mating connectors by engaging threads in a coupling ring with threads on a receptacle shell. (MIL-STD)

Thread Self-Locking Coupling
A coupling mechanism utilizing matching screw threads for mating and un-mating of cylindrical connectors incorporating an automatically actuated locking mechanism to prevent the coupling ring from becoming loose under vibration

Threaded Coupling
A means of coupling mating connectors by engaging threads in a coupling ring with threads on a receptacle shell.

Three Conductor Cable
Three insulated conductors assembled with other necessary cable components (shield, filler, etc.) to form a core, protected by an overall jacket.

Three-Phase Current
Current delivered through three wires, with each wire serving as a return for the other two.

Three-Phase Three-Wire System
An alternating current supply system comprising three conductors over which three-phase power is sent.

Three-Wire System
A DC or single-phase AC system comprising three conductors, one of which is maintained at a potential midway between the potential of the other two.

Threshold
A defined pass or fail value, i.e., the maximum or minimum value of insertion loss in dB or dBm.

Through-hole Technology
A method for constructing electronic circuits in which the components are inserted into holes drilled in printed boards and soldered to pads on the opposite side. Frequently abbreviated as THT. An alternate spelling is thru-hole.�

TIA
See Telecommunications Industry Association.

TIA/EIA
1) Telecommunications Industry Association/Electronic Industries Association; 2) North American Standards Organization.

TIA/EIA 568A or B
North American Commercial Building Telecommunications Wiring Standard.

TIA/EIA 569
North American commercial building standard for telecommunications pathways and spaces. Its purpose is to standardize specific design and construction practices within and between buildings which are in support of telecommunications media and equipment.

TIA/EIA 606
North American administration standard for the telecommunications infrastructure of commercial buildings. Its purpose is to provide guidelines for a uniform administration scheme for the cabling infrastructure.

Tie Wrap
A type of fastener, especially for binding several electronic cables or wires together, and to organize cables and wires. It consists of a sturdy Nylon tape with an integrated gear rack, and on one end a ratchet within a small open case. It is also referred to as a "cable tie", "strap", "rat belt", "mouse belt", or "zip tie".�

Tight Buffer
Type of cable construction whereby each glass fiber is tightly buffered by a protective thermoplastic coating to a diameter of 900m. Increased buffering provides ease of handling and connectorization.

Tight Buffer (Fiber Optic)
A material surrounding a fiber in a cable, holding it firmly in place.

Tight buffered cable
A type of cable with internal 900-micron coated fibers, such as breakout and distribution styles. Jacket materials vary but they are normally rated for indoor use to meet plenum, riser, and LSZH requirements.

Tightly-coupled mode
A low order or axial mode from either a laser or a LED. Low order modes cause less differential mode delay (higher bandwidth).

Time division multiple access (TDMA)
A data transmission method in which a number of individual transmitters in different locations share a transmission channel, each occupying the channel for a portion of the total time.

Time division multiplexing (TDM)
A digital technique for combining two or more signals into a single stream of data by sharing time.

Time-Division Multiple Access (TDMA)
The cellular industry established a TDMA digital standard in 1989. TDMA increases the channel capacity by chopping the signal into pieces and assigning each one to a different time slot. Current technology divides the channel into three time slots, each lasting a fraction of a second. Therefore, a single channel can be used to handle three simultaneous calls.

Time-Division Multiplex (TDM)
The process or device by which more than one signal can be sent over a single channel by using different time intervals for the different signals. This may be done by varying the pulse duration, pulse amplitude and pulse position.

Time, assembly
The time interval between the spreading of the adhesive on the substrate and the application of pressure or heat, or both, to the assembly. Same as closed assembly time.

Time, curing
The period of time during which an assembly is subject to heat or pressure, or both, to cure the adhesive.

Time, drying
The period of time during which an adhesive on a substrate or an assembly is allowed to dry with or without the application of heat or pressure, or both.

Time, Fixture
Time needed for adhesive to reach sufficient strength to allow pieces to be handled and moved.

Time, joint conditioning
The time interval between the removal of the joint from conditions of heat or pressure, or both, used to accomplish bonding and the attainment of approximately maximum bond strength. Sometimes called joint aging time.

Time, Open
Time during which the adhesive remains active without curing after being applied to the substrate.

Time, setting
The period of time during which an assembly is subjected to heat or pressure, or both to set the adhesive.

Tin (Sn)
A metallic element with atomic number 50. A common terminal plating material used on brass, copper and (over a layer of copper flash) on steel. It provides high conductivity at low cost and is often used on terminal components that will be in contact with aluminum to reduce galvanic corrosion.

Tin Overcoat (TOC)
Tinned copper wire, stranded, then coated with pure tin.

Tin-Lead
An alloy used for the majority of soldering operations in the electronics industry. Usually an alloy close to the eutectic composition (62% Sn, 38% Pb) is chosen to permit usage of the lowest possible soldering temperature thereby reducing risk of damage to temperature-sensitive components.

TINA Consortiun
Telecommunications Information Networking Architecture Consortium

Tinned Copper
Tin coating added to copper to aid in soldering and inhibit corrosion.

Tinned Wire
Copper wire that has been coated with a layer of tin or solder to facilitate soldering.

Tinning
The process of coating wires or contacts with a light layer of solder. This allow you to more easily melt them together when soldering.�

Tinsel
A type of electrical conductor comprised of a number of tiny threads, each thread having a fine, flat ribbon of copper or other metal closely spiraled about it. Used for small size cables requiring limpness and extra-long flex life.

Tinsel Wire
A low voltage, stranded wire where each strand is very thin conductor ribbon spirally wrapped around a textile yarn.

TM Forum
Telemanagement Forum

TMN
Telecommunications Managenment Network

TMRS
Traffic Measurement And Recording Systems

TNC (Threaded Neill Concelman)
Coaxial connector with screw type coupling mechanism. Available in 50 ohm and 75 ohm versions. Frequency range DC - 11 GHz (50 ohm) and DC - 1 GHz (75 ohm), respectively.

Token
A special data sequence that is continuously sent around the ring. The term "token" represents permission to transmit from one station to its downstream neighbor.

Token Bus
A bus topology that uses token passing as its contention method.

Token Passing
Moving a special combination of bits from station to station in a ring or bus when there is no traffic. When a workstation has the token, it may then use the network channel for communications.

Token Ring
A data link protocol type which implements media access control (MAC) by the circulation of a token around a complete ring network. Each station in the ring sequentially receives the opportunity to send data on the network as the token is passed around the network.

Token Ring LAN
A 4 or 16 Mb/s LAN standard based on token passing access protocol originally developed by IBM. Sometimes referred to as IEEE 802.5 or ISO 8802-5 standard.

Tolerance
The total amount by which a quantity is allowed to vary from nominal; thus,