F

F CONNECTOR

Std. 75ohm connector used on drop-cable.

F77

Fortran 77 compiler

FACTOR

The available space on a hard drive partition that Windows can address as physical memory.

FAL

File Access Listener

FAN-OUT (HEAVY DUTY) FIBER OPTIC CABLE

Tight buffered cable with 2, 4, 6, or 12 fibers

FAN-OUT (STANDARD DUTY) FIBER OPTIC CABLE

Tight buffered cable with 2, 4, 6, 12, 18, or 24 fibers

FAQ

FAQ is an acronym for "Frequently Asked Questions". A FAQ is typically a text on one subject organized as a list of common questions related to the subject and the anwers. FAQ's on many subjects are frequently posted to the newsgroup news.answers.

FARNET

Federation of American Research NETworks.

FAST-TRAC

Faster and Safer Travel Through Traffic Routing and Advanced Controls

FASTRAIN

See CCITT V.32bis.

FAT

File Access Table

FAULT TOLERANCE

The ability of a system to recover from an error, a failure, or a change in environmental conditions (such as loss of power). True fault tolerance provides for fully automatic recovery without disruption of user tasks or files, in contrast to manual means of recovery such as restoring data loss with tape backup files.

FCC

Federal Communications Commission

FCI

Frame Copied Indicator Bit

FCS

Frame Check Sequence

FDDI

See Fiber Distributed Data Interface

FDM

See Frequency Division Multiplexing.

FDX

See two-way simultaneous (full-duplex). See Full DupleX

FECN

See Forward Explicit Congestion Notification.

FEDERAL NETWORKING COUNCIL

(FNC) The body responsible for coordinating networking needs among U.S. Federal agencies.

FEP

See Front End Processor.

FER

Frame Error Rate

FERRULE

Tip or termination of a fiber-optic bundle.

FFST/2

See First Failure Support Technology/2.

FIBER DISTRIBUTED DATA INTERFACE

Uses fiber optics and is faster than Ethernet. 100Mbps - segment length <=2000m - network span <=200000m - no more than 1000 nodes per segment. Specifies 62.5/125um, with 50/125um, 82/125um, and 100/140um allowed as alternates. See Fiber Optic

FIBER OPTIC

Optical fiber cable is specified in terms of the diameter of the fiber core and the outer diameter of the cladding layer surrounding the core. See 10BASE-FL

FIBER OPTIC INTER REPEATER LINK

Primarily for connecting 10BASE-T hubs using fiber links. 10Mbps - segment length <=1000m

FID

Format Identifer

FIELD

One-half of a complete video frame, consisting of every other analog scan line.

FILE SERVER

A network node that usually consists of fixed-disk storage and a CPU, for storing programs and data shared by users on a network. File servers offer operating system-type file and print capabilities, while database servers provide database intelligence such as transaction processing, indexing, logging, security, and so on.

FILE TRANSFER PROTOCOL

(FTP) An error-checking protocol for file transfers (such as KERMIT, XMODEM, or YMODEM). It monitors information sent with each block of data. If the received data doesn't match the information used to check the quality of data, the system notifies the sender that an error has occurred and asks for a retransmission. It is the Internet standard, application-level protocol for transferring files from one computer to another. Usually FTP is implemented in application programs using the Telnet and TCP protocols. The server side requires a client login and password before it honors requests

FILE TRANSFER, ACCESS, AND MANAGEMENT

(FTAM) The OSI remote file service and protocol.

FILES =

Sets the number of files that MS-DOS can access at one time.

FILESET

A shared directory on an Extended Services server disk, and all files and directories within it.

FILL FACTOR

Indication of image-to-electron conversion efficiency; influenced by ratio of light-sensitive pixel area to total pixel area.

FILTERING (DSP)

A process used in both analog and digital image processing to reduce bandwidth. Filters can be designed to remove information content such as high or low frequencies, for example, or to average adjacent pixels, creating a new value from two or more pixels.

FILTERING (ETHERNET)

Process whereby an Ethernet switch or bridge reads the contents of a packet and then finding that the packet does not need to be forwarded, drops it. A filtering rate is the rate at which a device can receive packets and drop them without any loss of incoming packets or delay in processing.

FINGER

A client that retrieves information about an Internet user's account. A text message returns account information, including user name and last time logged in.

FIPS

Federal Information Processing Standard

FIRMWARE

Software that is programmed into a PROM or ROM chip to become part of the hardware function.

FIRST FAILURE SUPPORT TECHNOLOGY/2

(FFST/2) A software product that provides a set of Application Program Interfaces for OS/2 programs to invoke for aid in problem determination. Functions provided by FFST/2 include logging and displaying errors, formatting and routing alerts, and generating data dumps. FFSTl2 is included in the LAN Distance product packages.

FIXED CALLBACK

A type of Callback in which the telephone number to be dialed is always the same.

FIXED DISK

Also known as a hard disk.

FLAME

To express strong opinion and/or criticism of something, usually as a frank inflammatory statement in an electronic message.

FLASH ADC

An analog-to-digital converter whose output code is determined in a single step by a bank of comparators and encoding logic.

FLIP CHIP

See Controlled-collapse Chip Connection.

FLOATING GROUND

An electrical circuit common which is not at earth ground potential or the same ground potential as circuitry with which it interfaces. A voltage difference can exist between the floating ground and earth ground.

FLOOD

Transmitting a packet across each interface on a bridge or a router.

FLOW CONTROL

The mechanism that regulates the flow of data between two devices. Modems typically have two methods of flow control software flow control (XON/XOFF) and hardware flow control (CTS/RTS).

FLT

Fairlight

FM

Function Management

FM SYNTHESIS

A method of generating sound through frequency modulation. Can provide stereo. See Wavetable Synthesis.

FMD

Function Management Data

FMT

Simpel text formatter

FNC

See Federal Networking Council.

FOIR

See Fiber Optic Inter Repeater Link.

FOLD

Fold long lines for finite outpur device

FOLLOW ME

A feature (of the AT&T Merlin Legend system) that sends your calls to a co-worker's extension. Follow Me must be programmed from the extension where you are sending the calls

FONT

A collection of alphabetic and numeral characters in one size and one style, including all the letters, numbers, and punctuation marks. For example, Courier New is a font.

FONT FAMILY

In Windows, a group of typefaces with similar characteristics. The families that Windows recognizes for font installation are Roman, Swiss, Modern, Script, and Decorative. For example, Arial, Arial Bold, Arial Bold Italic, Arial Italic, Small Fonts, and MS Sans Serif are all part of the sans serif Swiss font family.

FORWARD EXPLICIT CONGESTION NOTIFICATION

A frame relay method in which the router notifies the destination device that it needs to send more frames than the line speed allows. This results in congestion at the router.

FORWARDING

Process whereby an Ethernet switch or bridge reads the contents of a packet and then passes that packet on to the appropriate attached segment. A forwarding rate is the time it takes the device to execute all the steps.

FPGA

Field Programmable Gate Array (Logic simulation acronym)

FPS

See Frames per second.

FR4

Designation for fiberglass/epoxy composite printed circuit board material.

FRACTALS

Along with raster and vector graphics, a way of defining graphics in a computer. Fractal graphics translate the natural curves of an object into mathematical formulas, from which the image can later be constructed.

FRAD

Frame Relay Access Devices

FRAGMENT

The small pieces into which a datagram is divided in order for a datagram to pass through a network that has a small maximum transfer unit (MTU). See also maximum transfer unit.

FRAGMENTATION

The process of breaking an IP datagram into smaller pieces to fit the requirements of a given physical network. See maximum transfer unit.

FRAME

Networking: A data structure consisting of fields defined by a protocol for the transmission of user and control data. A frame usually contains data plus address, control, and error-check information. Frame formatting implements an access protocol for the purpose of enabling communications between nodes on a LAN (Ethernet, Token Ring, ARCnet, and so on). On a LAN, this structure is frequently called a packet. However, a frame should not be confused with a packet, which is encapsulated within a frame for transport across a LAN. The terms 'frame' and 'packet' often are interchanged in common usage, especially by Novell, but have distinctly different functions and use distinctly different layers of protocol. Video: A single, complete picture in video or film recording. A video frame consists of two interlaced fields of either 525 lines (NTSC) or 625 lines (PAL/SEACAM), running at 30 frames per second (NTSC) or 25 frames per second (PAL/SEACAM).

FRAME GRABBER

A device that "captures" and potentially stores one complete video frame. Also known as Frame Storer.

FRAME RATE

The speed at which video images are displayed. Number of times per second that frame is scanned

FRAME RELAY

Frame Relay technology was developed for Broadband Integrated Services Digital Network (B-ISDN). It can provide higher transfer-data rates by eliminating much of the overhead inherent in an X.25 network. Multiplexing and switching are provided at the lower data link layer rather than the network layer. The flow control and error control that exists between packet switch nodes for X.25 does not exist in Frame Relay. Frame Relay relies on higher-level software mechanisms to provide this service if necessary, and assumes that the media used for data transmission is inherently reliable and much of the error checking can be eliminated. You can connect different topologies transparently by employing the frame relay mechanism to route the data traffic between users. You usually implement frame relay between multiple routers on separate LANs. This keeps unnecessary traffic, such as Routing Information Protocol (RIP) and Service Advertising Process (SAP) packets, from leaving your local networks and cascading across your remote networks. Frame relay isn't a broadcast-based protocol-it's based on a non-broadcast multi-access (NBMA) network. This means that the frame relay can carry multiple virtual circuits across a single connection point, increasing the total bandwidth available for transmitting packet frames. These virtual circuits are called either switched virtual circuits (SVC) or permanent virtual circuits (PVC). If an error occurs during the transmission of a frame, the protocol discards the packet. Frame relay places the burden of error correction on the destination and sending computer systems so the network has to commit less processor overhead to ensuring data integrity. Frame relay is based on the principles of packet switching. When you send data packets to a frame relay service, the service routes the packet toward its destination. In addition, the frame relay service: 1 divides the data into variable-length frames, including all addressing information necessary to deliver the frame packet to the destination site. 2 reads the addressing information within the frame and routes the packet to the appropriate output link. 3 checks the status of the frame relay switch (if the switch is congested, the frame relay service sets the congestion notification bit, halting the sending of more frames until the congestion eases). 4 places the frames into the frame relay network. 5 monitors the frame check sequence to ensure proper delivery. Frame relay performs all these functions at layer 2, the DataLink layer of the OSI network model. On the other hand, packet switching networks such as X.25 access information from both the second and third layers of the frame packet.

FRAMES PER SECOND

This term is most often used when talking about the speed of video capture and playback. It refers to the number of frames per second of video images displayed on the screen. The higher the frame rate, the more fluid the motion appears. The highest, or best, quality frame rate available is 30 fps. Lower frame rates (below 10) still appear as motion, but are noticeably "jerky," while zero fps is a still frame See Inter Exchange Carrier. Film is 24 FPS, NTSC is 30 FPS and PAL/SECAM is 25 FPS.

FRAMING

Dividing data for transmission into groups of bits, and adding a header and a check sequence to form a frame.

FREE TOKEN

A unique sequence of bits transmitted on a token ring network. Each node must wait for the token before it transmits.

FREQUENCY DIVISION MULTIPLEXING

See Broadband LAN.

FRICC

Federal Research Internet Coordinating Committee. Now replaced by the FNC.

FRONT END

Synonymous with an application user interface. Compare with Back End.

FRONT-END PROCESSOR

(FEP) See Communications Controller.

FT1

Fractional T1

FTAM

See File Transfer Access and Management

FTP

See File Transfer Protocol

FTP-DATA

File Transfer Protocol Data

FULL DUPLEX

Biderectional, simultaneous communications.

FULL-MOTION VIDEO

Video reproduction at 30 frames per second (NTSC-original signals) or 25 frames per second (PAL-original signals).

FUNCTIONAL ADDRESS

A Token-Ring destination address used to identify widely-used functions. It is typically used to specify the destination for a broadcast message.

FWIW

For what it's worth

FYI

For Your Information