Telecommunications terms starting with I

449 terms

instructional television fixed station A fixed station operated by an educational organization and used primarily for the transmission of visual and aural instructional, cultural, and other…
instrument landing system (ILS) A radio-navigation system which provides aircraft with horizontal and vertical guidance just before and during landing and, at certain fixed points…
instrument landing system glide path A system of vertical guidance embodied in the instrument landing system which indicates the vertical deviation of the aircraft from its optimum path of…
instrument landing system localizer A system of horizontal guidance embodied in the instrument landing system which indicates the horizontal deviation of the aircraft from its optimum path…
insulated wire Telecommunications plant containing from one to six paired conductors, and possibly a shield. Wire may be found in either aerial or buried installations.
integrated circuit (IC) An electronic circuit that consists of many individual circuit elements, such as transistors, diodes, resistors, capacitors, inductors, and other active…
integrated digital network (IDN) A network that uses both digital transmission and digital switching.
integrated ground plane A set of interconnected frames that is intentionally grounded via multiple connections to a ground reference.
integrated optical circuit (IOC) A circuit, or group of interconnected circuits, consisting of miniature solid-state optical components on semiconductor or dielectric substrates.
integrated services digital network See ISDN.
integrated station A terminal device in which a telephone and one or more other devices, such as a video display unit, keyboard, or printer, are integrated and used over a…
integrated system A telecommunication system that transfers analog and digital traffic over the same switched network.
integrated voice and data terminal (IVDT) See integrated station.
integrating network A network (circuit) that produces an output waveform that is the time integral of the input waveform.
Integrity Guarding against improper information modification or destruction, and includes ensuring information non-repudiation and authenticity.
integrity check value [A] checksum capable of detecting modification of an information system (IS). [INFOSEC-99]
intelligent agent Synonym droid.
intelligent network (IN) 1. A network that allows functionality to be distributed flexibly at a variety of nodes on and off the network and allows the architecture to be modified…
intelligent network (IN) supported service A service provided using the capabilities of the intelligent network. [T1.667-1999]
intelligent network application protocol (INAP) A protocol for intelligent network applications contained in Layer 7 (the Application Layer of the OSI model). [T1.667-1999]
intelligent peripheral (IP) A functional component that may be used most efficiently when accessed locally. 2.
intelligibility For voice communications, the capability of being understood. Note: Intelligibility does not imply the recognition of a particular voice.
intelligible crosstalk Crosstalk from which information can be derived.
INTELSAT Abbreviation for International Telecommunications Satellite Organization. [47 CFR 0.453]
Intensity With regards to light, intensity is the energy moving through a region of area per unit of time.
intensity modulation (IM) In optical communications, a form of modulation in which the optical power output of a source is varied in accordance with some characteristic of the…
inter-LATA 1. Between local access and transport areas (LATAs). 2. Services, revenues, and functions associated with telecommunications that originate in one LATA…
inter-satellite service A radiocommunication service providing links between artificial Earth satellites. [NTIA] [RR] [47CFR]
interaction crosstalk Crosstalk caused by coupling between carrier and noncarrier circuits. Note: If the interaction crosstalk is, in turn, coupled to another carrier circuit…
interactive Pertaining to a communications environment in which more than one party is equipped and ready to participate actively in a session or a protocol.
interactive data transaction A unidirectional message, transmitted via a data channel, that requires a response in order for work to proceed logically.
interactive service In an integrated services digital network (ISDN), a telecommunications service that facilitates a bidirectional exchange of information among users or…
Interactive Video Data Service (IVDS) A communication system, operating over a short distance, that allows nearly instantaneous two-way responses by using a hand-held device at a fixed…
interblock gap On a data recording medium, an area used to indicate the end of a block or physical record.
intercept To stop a telephone call directed to an improper, disconnected, or restricted telephone number, and to redirect that call to an operator or a recording. 2.
intercept call request An operator services call request initiated by the network because of the service condition of the line of the called party (e.g.
interchange Mutual acceptance and exchange of messages between entities. [After X9.24]
interchange circuit A circuit that facilitates the exchange of data and signaling information between data terminal equipment (DTE) and data circuit-terminating equipment…
Interchangeability A condition which exists when two or more items possess such functional and physical characteristics as to be equivalent in performance and durability…
interchangeable connectors Connectors that share common installation geometry and have the same transmission performance.
Interchangeable NPAs Refers to an industry plan to expand substantially the supply of Numbering Plan
intercharacter interval In asynchronous transmission, the time interval between the end of the stop signal of one character and the beginning of the start signal of the next…
intercom A telephone apparatus by means of which personnel can talk to each other within an aircraft, tank, ship, or activity. [JP 1-02] 2.
interconnect facility In a communications network, one or more communications links that (a) are used to provide local area communications service among several locations and…
interconnecting networks (ICNs) Two or more networks connected for purposes of call processing. [T1.207-1998]
Interconnection A connection or link between power systems that enables them to draw on each other's reserve capacity in time of need.
interconnectivity See interconnection.
interdigit interval A multifrequency (MF) and dual tone multifrequency (DTMF) signal timing interval that is equal to the sum of the fall time, signal-off time, and rise time.
interdomain authority an authority recognized by two or more Security Administrations as a trusted source of security information used between the respective Security Domains…
interest group A gathering or category of network users who have a similar interest in a particular topic and who share their opinions with each other via email or an…
interexchange carrier (IXC or IC): 1. A communications common carrier authorized to provide interexchange telecommunications services within world zone 1 using the North American…
interexchange channel A circuit which is included in the interexchange transmission equipment. [47 CFR Pt.36-A]
interexchange transmission equipment The combination of (a) interexchange cable and wire facilities, (b) interexchange circuit equipment and, (c) associated land and buildings. [47 CFR Pt.
interface (I/F) 1. In a system , a shared boundary, i.e., the boundary between two subsystems or two devices. 2.
interface data The parameter within a primitive that is the unit of information transferred to/from the upper layer or sublayer in a single interaction. [T1.629-1999]
interface functionality In telephony, the characteristic of interfaces that allows them to support transmission, switching, and signaling functions identical to those used in the…
interface message processor (IMP) A processor-controlled switch used in packet-switched networks to route packets to their proper destination.
interface payload In integrated services digital networks (ISDN), the part of the bit stream through a framed interface used for telecommunications services and signaling.
interface point Synonym point of interface.
interface rate The gross bit rate of the signal at the boundary between the physical layer and the physical medium. [T1.107-1988]
interface standard A standard that describes one or more functional characteristics (such as code conversion, line assignments, or protocol compliance) or physical…
interference a proceeding, conducted before the Board of Patent Appeals and Interferences (Board), to determine priority of invention between a pending application and…
interference emission Emission that results in an electrical signal's being propagated into, and interfering with the proper operation of, electronic or electrical equipment.
interference filter An optical filter that reflects one or more spectral bands or lines and transmits others, while maintaining a nearly zero coefficient of absorption for…
interfering contour The locus of points surrounding a transmitter where the predicted median field strength of the signal from that transmitter is the maximum field strength…
interferometer An instrument that uses the principle of interference of electromagnetic waves for purposes of measurement.
interferometry The branch of science devoted to the study and measurement of the interaction of waves, such as electromagnetic waves and acoustic waves.
interframe time fill In digital data transmission, a sequence of bits transmitted between consecutive frames.
interlaced scanning In raster-scanned video displays, a scanning technique in which all odd-numbered scanning lines are first traced in succession, followed by the tracing of…
interlacing Synonym interlaced scanning.
interleaving The transmission of pulses from two or more digital sources in time-division sequence over a single path.
interlocal trunk A circuit between two local central office units, either manual or dial. Interlocal trunks may be used for either exchange or toll traffic or both.
intermediate certificates In cryptology, certificates in a certificate chain other than the first or end certificate.
intermediate distribution frame (IDF) In a central office or customer premises, a frame that (a) cross-connects the user cable media to individual user line circuits and (b) may serve as a…
intermediate element In a network, a line-unit-line termination (LULT) or a line-unit-network termination (LUNT).
intermediate field Synonym intermediate-field region.
intermediate frequency (IF) A frequency to which a carrier frequency is shifted as an intermediate step in transmission or reception.
intermediate language In computer programming, a target language into which all or part of a single statement or a source program--in a source language--is translated before it…
Intermediate Network Any interconnecting network(s) between the originating network and terminating network.
Intermediate Numbers: Intermediate numbers are numbers that are made available for use by another telecommunications carrier or non-carrier entity for the purpose of providing…
intermediate operating system In some operating system (OS) architectures, the OS functions that may be implemented through a central element and one or more remote elements that may…
intermediate system A system that provides an Open Systems Interconnection--Reference Model (OSI--RM) Network Layer relay function in which data received from one…
intermediate translation signaling point (ITSP) A translation signaling point (TSP) that translates the global title (as received or after changing to another global title) to identify the next TSP in…
intermediate trunk (IT) A channel mapping designation that ranges between 1 and 216 and relates the digital circuit multiplication equipment (DCME) transmission trunk to an…
Intermediate Zone The subsurface water zone below the root zone and above the capillary fringe.
intermediate-field region For an antenna, the transition region--lying between the near-field region and the far-field region--in which the field strength of an electromagnetic…
intermediate-level language In computer, communications, and data processing systems, a programming language that (a) is less machine-oriented than a machine language, (b) is not so…
intermittent service area The area receiving service from the groundwave of a broadcast station but beyond the primary service area and subject to some interference and fading.
intermodal delay distortion Synonym multimode distortion.
intermodal dispersion Incorrect synonym for multimode distortion.
intermodal distortion Synonym multimode distortion.
intermodulation (IM) The production, in a nonlinear element of a system, of frequencies corresponding to the sum and difference frequencies of the fundamentals and harmonics…
intermodulation distortion Nonlinear distortion characterized by the appearance, in the output of a device, of frequencies that are linear combinations of the fundamental…
intermodulation noise In a transmission path or device, noise, generated during modulation and demodulation, that results from nonlinear characteristics in the path or device.
intermodulation product In the output of a nonlinear system, a frequency produced by intermodulation of harmonics of the frequencies present in the input signal.
internal bias In a start-stop teletypewriter receiving mechanism, bias generated locally by the mechanism, and which has the same effect on the operating margin as bias…
internal call A call placed within a private branch exchange (PBX) or local switchboard, i.e., not through a central office in a public switched network.
internal memory In a computer, all of the storage spaces that are accessible by a processor without the use of the computer input-output channels.
internal photoelectric effect A photoconductive or photovoltaic effect.
internal storage Synonym internal memory.