Intermediate ZoneThe subsurface water zone below the root zone and above the capillary fringe.
intermediate-field regionFor 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 languageIn 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 areaThe area receiving service from the groundwave of a broadcast station but beyond the primary service area and subject to some interference and fading.
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 distortionNonlinear distortion characterized by the appearance, in the output of a device, of frequencies that are linear combinations of the fundamental…
intermodulation noiseIn a transmission path or device, noise, generated during modulation and demodulation, that results from nonlinear characteristics in the path or device.
intermodulation productIn the output of a nonlinear system, a frequency produced by intermodulation of harmonics of the frequencies present in the input signal.
internal biasIn 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 callA call placed within a private branch exchange (PBX) or local switchboard, i.e., not through a central office in a public switched network.
internal memoryIn a computer, all of the storage spaces that are accessible by a processor without the use of the computer input-output channels.
International Atomic Time (TAI)The time scale established by the Bureau International des Poids et Mesures (BIPM--International Bureau of Weights and Measures in Sevres, France) on the…
international carrier (INC)A carrier authorized to provide telecommunications services outside World Zone 1 using the international dialing plan; however, the carrier has the option…
international fixed public control serviceA fixed service carried on for the purpose of communicating between transmitting stations, receiving stations, message centers or control points in the…
international prefixThe combination of digits to be dialed by a calling subscriber making a call to a subscriber in another country to obtain access to the automatic outgoing…
international routing codeA 3-digit code within the North American numbering plan, beginning with 1, that classifies international calls as requiring either regular or special…
International System of Units (SI)The modern form of the metric system, which has been adopted by the United States and most other nations.
International Telecommunication Union (ITU)An international organization under the UN headquartered in Geneva concerned with telecommunications that develops international data communications…
International Telegraph Alphabet Number 5 (ITA-5)An alphabet in which (a) 128 unique 7-bit strings are used to encode upper- and lower-case letters, 10 decimal numerals, special signs and symbols…
InternationalizationThe process of designing and developing a product with a set of features, functions, and options intended to facilitate the adaption of the product to…
InternautSlang term for a user of the Internet. Synonym cybernaut.
InternetA worldwide network of networks that all use the TCP/IP communications protocol and share a common address space.
Internet [the]A worldwide interconnection of individual networks a) with an agreement on how to talk to each other, and b) operated by government, industry, academia…
Internet addressIn The Internet protocol, the decimal-numeric, fixed-length address that identifies the hosts of data sources, and, specifically, a communication port.
Internet Architecture Board (IAB)The technical body that oversees the development of the Internet suite of protocols (commonly referred to as "TCP/IP"), and that has two task forces (the…
Internet Assigned Numbers Authority (IANA)An organization, directed by the Internet Architecture Board, that assigns IP numbers and protocol parameters such as port, protocol, and enterprise…
Internet assistantCommercial software, written in HTML, that combines the functions of a file-conversion tool and a Web browser.
Internet phoneA combination of software and hardware that allows a user to approximate a telephone conversation over an Internet connection instead of using a…
Internet protocol (IP)A DOD standard protocol designed for use in interconnected systems of packet-switched computer communication networks.
Internet protocol (IP) spoofingThe creation of IP packets with counterfeit (spoofed) IP source addresses. 2. A method of attack used by network intruders to defeat network security…
internetworkingThe process of interconnecting two or more individual networks to facilitate communications among their respective nodes.
InterNICContraction of Internet Network Information Center. The association of providers of domain-name registration, information, and database services to the…
interoffice trunkA single direct transmission channel, e.g., voice-frequency circuit, between central offices.
InteroperabilityThe ability of systems, units, or forces to provide services to or accept services from other systems, units, or forces and to use the services so…
interoperability standardA document that establishes engineering and technical requirements that are necessary to be employed in the design of systems, units, or forces and to use…
interoperationThe use of interoperable systems, units, or forces. [JP 1-02]
interpolation gainThe input trunk channel multiplication ratio that is achieved through DSI. The interpolation gain is the ratio of the number of input transmission trunks…
interposition trunkA single direct transmission channel, e.g., voice-frequency circuit, between two positions of a large switchboard to facilitate the interconnection of…
interpretTo translate and to execute each source language statement of a computer program before translating and executing the next statement.
interrogationThe transmission of a signal or combination of signals intended to trigger a response. 2.
interruptAn asynchronous message sent to a process or thread that interrupts what it is currently doing.
interruption controlA system that monitors a pilot for interruptions on frequency division multiplexing (FDM) systems and that transmits an indication to the switching…
interswitch trunkA single direct transmission channel, e.g., voice-frequency circuit, between switching nodes.
intersymbol interferenceIn a digital transmission system, distortion of the received signal, which distortion is manifested in the temporal spreading and consequent overlap of…
intertoll circuitsCircuits between toll centers and circuits between a toll center and a tandem system in a different toll center area. [47 CFR Pt.36-A]
intertoll trunkA single direct transmission channel, e.g., voice-frequency circuit, between two toll offices.
interworking functionsMechanisms that mask differences in physical, link, and network technologies by converting (or mapping) states and protocols into consistent network and…
intra-LATAWithin the boundaries of a local access and transport area (LATA).
intramodal distortionIn an optical fiber, distortion caused by dispersion, such as material or profile dispersion, of a given propagating mode. [After 2196]
intranetA private network that uses Internet-related technologies to provide services within an organization.
intraoffice trunkA single direct transmission channel, e.g., voice-frequency circuit, within a given switching center.
intrinsic joint lossOf nonidentical optical fibers joined by a splice or a mated pair of connectors, the power loss attributable to manufacturing variations, in such…
intrinsic noiseIn a transmission path or device, that noise inherent to the path or device and not contingent upon modulation.
intrusive measurementsMeasurements that require that the facility be taken out of service and made unavailable to the user. [T1.Rpt25-1993]
invalid frameA frame for which one or more of the following conditions apply: the frame is not properly bounded by flags; the frame does not consist of an integral…
Inventorya detailed accounting of all items within a specified location. Examples include but are not limited to: evidence in the evidence vault, evidence in the…
inverse adaptive quantizerIn the encoder and the feedback path of the decoder, the process that maps the core bits into a quantized difference signal.
inverse multiplexerA functional unit capable of accessing and combining two or more low-speed circuits into a virtual broadband circuit, up to and including an aggregate…
Inverse Square LawThe law that states when thermal or nuclear radiation is uniformly emitted from a point source, the amount received per unit area at any given distance…
inverted positionIn frequency-division multiplexing, a position of a translated channel in which an increasing signal frequency in the untranslated channel causes a…
InverterA device that converts direct current electricity (from for example a solar photovoltaic module or array) to alternating current for use directly to…