Fiber Optic Center Glossary
There are currently 191 names in this directory beginning with the letter I.
A device that arbitrates the I/O channel and controls data transfer between devices attached to the channel.
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.
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.
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.
Guidelines describing the physical and data link layers of the OSI network model for various topologies.
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
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.
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.
Device used to punch new conductor onto ID's. This tool is typically equipped with a cutting blade for either 66 or 110 blocks.
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.
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.
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.
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.
Intermittent, short, high frequency, high amplitude pulses that are induced into a transmission line. Can cause data corruption and in some cases hardware damage.
The voltage breakdown of insulation under voltage surges on the order of microseconds in duration.
An insulation test in which the voltage applied is an impulse voltage of specified wave shape.
Incumbent local exchange carrier (ILEC)
The dominant phone carrier within a geographic area that provides local exchange service to that area.
The part of a crimping die, usually the moving part, which indents or compresses the contact barrel. (MIL-STD)
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.
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.
An electric current set up in a circuit by cutting lines of force; a current caused by electromagnetic induction.
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.
An influence exerted by a charged body or by a magnetic field on adjacent bodies without apparent communication.
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.
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.
A high bandwidth switched network topology currently being developed for Storage Area Networks (SANS).
The range of electromagnetic wavelengths between the visible part of the spectrum (750 nm) and microwaves (30 µm).
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.
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)
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.
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.
The central conductive member in a coaxial structure, such as the center contact in a coaxial connector.
Usually a nonmetallic pathway that may be placed within a duct to facilitate initial and subsequent placement of multiple cables in a single duct.
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.
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.
That part which holds the contacts in their proper arrangement and electrically insulates them from each other and from the shell.
Insert Electrical Connector
An insulating element with or without contacts designed to position and support contacts in a connector. (MIL-STD
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.
The element that holds connector contacts in their proper arrangement and electrically insulates the contacts from one another and from the connector shell.
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.
A device which conforms to the gaging limits specified on the applicable tool specification sheet.
A hole placed at one end of a crimp contact barrel to insure proper insertion of the conductor prior to crimping. (MIL-STD)
A microscope or digital scope that inspects ferrule and termini fiber endfaces for polishing quality, damage, or contamination.
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.
A solderless terminal with an insulated sleeve over the barrel to prevent a short circuit in certain installations.
A device which mechanically couples and electrically insulates the sheath and armor of contiguous lengths of cable.
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.
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.
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.
A non-metallic covering applied around a metallic conductor or optical fiber to provide electrical isolation and/or moisture protection.
Area of a terminal, splice or contact that has been formed aroind the insulation of the wire.
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.
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.
Extended cylinders at the rear of crimp-type contacts designed to accept the bared wire and a small length of its insulation.
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).
A method of crimping whereby lances cut the insulation of the wires and enter into the strands to make electrical contact.
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.
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.
The portion of a barrel similar to an insulation grip except that it is not compressed around the conductor insulation. (MIL-STD)
All of the insulation materials used to insulate a particular electrical or electronic product.
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.
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.
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.
Optical mixing chamber fitted to Detector, allowing use multi-channel connectors like MPO.
Buildings that maximize the efficiency of its occupants and allow effective management of resources with minimum life-time costs (Source: European Intelligent Building Group).
A terminal which contains an integral microprocessor with some logical capability.
Characteristic of connectors in which a connector half of one manufacturer will mate directly with a connector half manufactured by a different company.
1) Center to center conductor spacing is paired wire or 2) center to center spacing between conductors in a flat cable.
A network that provides communications between buildings, e.g., college campus, office park, or military installation.
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.
A connection scheme that provides for the direct connection of individual cables to another cable or to an equipment cable without a patch cord.
The physical wiring between components (outside a module) between modules, between units or between larger portions of a system or systems.
Interexchange carrier (IXC)
Any common carrier that provides long-distance services, i.e., Sprint or AT&T.
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)
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.
A sealing of mated connectors over the whole area of the interface to provide sealing around each contact. (MIL-STD)
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.
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.
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.
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.
An adhesive that sets in the temperature range from 31 to 99°C (87 to 211°F).
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.
The intended electrical path contains an unintended gap that appears and disappears when the assembly is flexed.
An unintended connection between 2 or more parts which appears and disappears when the assembly is flexed.
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.
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.
The connection of multiple networks for data interchange. This is normally accomplished with interface devices such as bridges, brouters and gateways.
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.
In cable construction, the space, valley or void left between or around the cable components.
Voids or valleys between individual strands in a conductor or between insulated conductors in a multiconductor cable. Space between adjacent structures.
A network that provides communications within a building; often referred to as the riser backbone in vertical buildings.
intrinsic viscosity/limiting viscosity number
The limiting value of the reduced viscosity or the inherent viscosity at infinite dilution of the polymer. (IUPAC)
A chain polymerization in which the kinetic-chain carriers are ions. Usually, the growing chain ends are ions. (IUPAC)
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.
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.
A polyelectrolyte in which a small but significant proportion of the constitutional units carry charges. (IUPAC)
A worldwide organization that sets standards, specifications and guidelines for PCB design, manufacture and assembly.
A soldering process that uses infrared (IR) light with a wavelength between visible light and microwave radiation as its energy source.
When connector bodies or other components prevent the infrared energy from directly striking some solder joints, causing non-uniform heading.
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.
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.
A macromolecule in which the constitutional units are not all identical. (IUPAC)
ISDN (Integrated Service Digital Network)
A digital data communications network providing full integration of data, voice and video.
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.
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.
The delivery of fixed length units of information at fixed time intervals relative to a time reference.
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.
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.
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)