fortuitous conductorAny conductor that may provide an unintended path for signals. Note: Examples of fortuitous conductors are water pipes, wires, cables, and metal building…
fortuitous distortionDistortion resulting from causes generally subject to laws concerning random occurrences.
forumA computer conference devoted to a specific subject, having an initiator, members, readers, and possibly moderators. [2382-pt.
ForwardTo redirect a received email to another email address.
forward busyingIn a telecommunications system, a feature in which supervisory signals are forwarded in advance of address signals in order to seize assets of the system…
forward channelThe channel of a data circuit that transmits data from the originating user to the destination user.
Forward CipherOne of the two functions of the block cipher algorithm that is determined by the choice of a cryptographic key.
forward echoIn a transmission line, an echo propagating in the same direction as the original wave and consisting of energy reflected back by one discontinuity and…
Forward Edge of the Battle Area (FEBA)The foremost limits of a series of areas in which ground combat units are deployed, excluding the areas in which the covering or screening forces are…
forward error correction (FEC)A system of error control for data transmission wherein the receiving device has the capability to detect and correct any character or code block that…
Forward FundingCarry-over of RDT&E funding into second year of appropriations availability. Requires permission from high authority.
forward indicator bit (FIB)A bit in a signal unit which indicates the start of a retransmission cycle. [T1.226-1992]
forward proxyA NetCache appliance configured as an intermediary server that accepts requests from clients and forwards them to a Web server or, if appropriate…
forward recoveryThe data reconstitution of a later version of data by using an earlier version and data recorded in a journal. [2382-pt.8]
forward scatterThe deflection--by diffraction, nonhomogeneous refraction, or nonspecular reflection by particulate matter of dimensions that are large with respect to…
forward secrecyThe confidence that the compromise of a long-term private key does not compromise any earlier session keys. [After X9.42]
forward sequence number (FSN)A field in a signal unit used to identify the transmitted message signal units. [T1.226-1992]
forward signalA signal sent in the direction from the calling to the called station, i.e., from the original data source to the original data sink.
ForwardsThis feature indicates that the provider in question can also automatically forward incoming emails to another email account.
Foundation ProfileThe Foundation Profile is a Java ME profile specification that builds on CDC. It adds additional classes and interfaces to the CDC APIs but does not go so…
four-wire circuitA two-way circuit using two paths so arranged that the respective signals are transmitted in one direction only by one path and in the other direction by…
four-wire repeaterA repeater, consisting of two amplifiers, one associated with each direction, used in a four-wire circuit.
four-wire terminating setA balanced transformer used to perform a conversion between 4-wire and 2-wire operation.
Fourier analysisThe definition of a periodic waveform of arbitrary shape as a summation of sine waves having specific amplitudes and phases, and having frequencies…
Fourth Generation LanguageA programming environment that produces both screen and report utilities for use by lower-level programming environments.
fox messageA standard test message that includes all the alphanumerics on a teletypewriter and also function characteristics (yyspace, figures shift, letters shift).
FQDNFully Qualified Domain Name. The complete name of a specific computer on the Internet, consisting of the computer's host name and its domain name.
FQDN (fully qualified domain name)A Domain Name System (DNS) that has been stated unambiguously to indicate with certainty its location in the domain namespace tree.
fractional frequency fluctuationThe deviation of the frequency of an oscillator from its nominal constant frequency, normalized to the nominal frequency.
fractional frequency offsetA measure of the deviation of the frequency of a signal from a reference, expressed as a ratio.
fractional T1In telecommunications, a portion of the 1.544 Mb/s (T1-aggregate) bit stream; the available fractions being determined by the type of multiplexer used to…
FragmentationProcess by which habitats are increasingly subdivided into smaller units, resulting in their increased insularity as well as losses of total habitat area.
Fragmentation WarheadA warhead, which releases small solid objects to damage or destroy its targets.
FrameThe stationary portion of a window unit that is affixed to the facade and holds the sash or other operable portions of the windows.
frame alignmentIn the reception of framed digital data, the extent to which a received frame is correctly aligned with respect to the clock at the receiver. 2.
frame durationThe time between the beginning of a frame and the end of that frame. Note: For fixed-length frames, at a fixed data rate, frame duration is constant.
frame grabberA device that can seize and record a single frame of video information out of a sequence of many frames.
frame matchingThe process of comparing one sequence of frames with another sequence of frames in order to determine the correspondence between frames in each sequence…
frame overheadBits (binary digits) that are added at regular intervals to a digital signal at the sending end of a digital link and used to provide network functions…
frame pitchThe distance, time, or number of bits between corresponding points, i.e., significant instants, in two consecutive frames. [From Weik '89]
frame rateThe number of frames transmitted or received per unit time. Note 1: The frame rate is usually expressed in frames per second.
frame relayAn interface protocol for statistically multiplexed packet-switched data communications in which (a) variable-sized packets (frames) are used that…
frame relaying protocol data unit (FPDU)A data unit exchanged at the user-network interface and having a format based on that defined in CCITT Recommendation Q.921 (1988) (ANSI T1.602). [T1.
frame sizeThe number of octets after the address field and before the frame check sequence (FCS) field in a frame.
frame slipIn the reception of framed data, the loss of synchronization between a received frame and the receiver clock, causing a frame misalignment event, and…
frame synchronizationOf a received stream of framed data, the process by which incoming frame alignment signals, i.e., distinctive bit sequences, are identified, i.e.
frame synchronization patternIn digital communications, a prescribed recurring pattern of bits transmitted to enable the receiver to achieve frame synchronization.
frame-alignment signalIn the transmission of data frames, a distinctive sequence of bits used to accomplish frame alignment.
frame-alignment time slotA time slot occupying the same relative position in every frame and used to transmit the frame alignment signal. [T1.107-1988]
frame-rate conversionWith respect to television or other video display technologies, the process of transforming from one standard frame rate to another, using an algorithm.
framed interfaceAn interface through which information flow is partitioned into physical, periodic frames consisting of overhead information and an information payload.
FramesAn HTML technique for combining two or more separate HTML documents within a single web browser screen.
FramesetA web page that is made up of frames. A useful analogy: if the individual frames that make up the frameset are the 'children,' then the frameset is the…
FramingThe structural materials and elements used to construct a wall.
framing bitA bit used for frame synchronization. 2. In a bit stream, a bit used in determining the beginning or end of a frame.
Free Electron Laser (FEL)A type of laser, which generates radiation by the interaction of an electron beam with a static magnetic or electric field.
free netA radio net in which any station may communicate with any other station in the net without first obtaining the permission of the net-control station.
Free RocketA rocket not subject to guidance or control in flight.
free routingThe routing of messages in such a manner that they are forwarded toward their destination or addressee over any available channel without dependence upon…
free spaceA theoretical concept of space devoid of all matter. Note: Free space also implies remoteness from material objects that could influence the propagation…
free text searchA search in which the search term is expressed as free-form text.
free-running capabilityIn a synchronized oscillator, the capability to operate in the absence of a synchronizing signal.
free-space couplingCoupling of magnetic, electric, or electromagnetic fields that are not confined to a conductor.