Glossary-B
A Data Communication Historical Series
By Bob Pollard

HOME                    INDEX

B CARRIER:

Most areas of the US will have two cellular phone carriers, each of which operates on a different frequency band. One is designated the ‘A Carrier’ and the other will be designated the ‘B’ carrier. In some areas there may be only one carrier which may be designated A or B.

B3ZS:

See Bipolar Three Zeros Substitution

B8ZS:

See Bipolar Eight Zeros Substitution or Bipolar With Eight Zero Substitution

BACKBONE:

1) The primary connectivity mechanism for a hierarchical distributed system.

2) The network of broadband connections between network switches.

3) A high-capacity data transmission network that links together other networks of a lower data transmission capacity.

4) Routers used for packet switching in the Internet.

5) Part of a network that acts as the primary path for traffic (data) that is usually sourced from, and destined for, other networks

BACKBONE NETWORK:

The high-density (capacity) portion of a network that connects primary nodes

BACK DOOR:

‘Trapdoor’ a feature often built into programs to allow special privileges normally denied to users of the program. Often programmers build back doors so they can fix bugs. If hackers or others learn about a back door, the feature may pose a security risk.

BACK END:

The server part of a client/server application(s): It provides services across the network that has been requested by the client. For example, a Back End may be a database server that responds to Structured Query Language (SQL) requests from a workstation running a front-end application.

BACK END NETWORK:

The interconnection of mainframe computers to mass-storage devices; example: high-speed controllers and file servers.

BACK END PROCESSES:

Refers to the functions performed by a database server in response to directions from an application running on an end user Personal Computer (PC).

BACKGROUND:

The screen background image used on a graphical user interface such as Windows: Any pattern or picture that can be stored as a bitmap (.bmp) file can be set as a screen background.

BACKGROUND PROCESSING:

Computer processing taking place when no real time higher priority entry is waiting to be processed. A higher priority process or device interrupt would take precedence over the background processing.

BACKGROUND SCANNING:

A feature in some anti-virus software to automatically scan files and documents as they are created, opened, closed or executed

BACKGROUND TASK or MODE:

1) A secondary function performed by a computer without interrupting its current or primary task.

2) Virus action: A task executed by the system but generally remains invisible to the user. The system usually assigns background tasks a lower priority than foreground tasks. Some malicious software is executed by a system as a background task so the user does not realize unwanted actions are occurring. See Background Processing.

BACK HAUL:

1) Refers to an indirect or less expensive routing of a call through a network; for example, a link between a central office and a main microwave, multiplex station or switching center where forward distribution occurs.

2) A method in which telephony signaling is reliably transported from a gateway to a Media Gateway Controller across a packet-switched network.

BACKHAULING:

An action, also called signal tunneling, where telephony signals are passed from a gateway to a separate control media for processing. The gateway may not interpret the signaling information.

BACKOFF / BACK OFF TIME:

1) Refers to a workstation transmission delay period immediately following a network collision in a Carrier Sense Multiple Access/Collision Detection (CSMA/CD) environment.

2) The random retransmission delay, enforced by MAC protocols, after a network node with data to transmit determines that the physical medium is already in use.

BACK ORIFICE:

Back Orifice is a program developed and released by The Cult of the Dead Cow (cDc). It is not a virus; it is a remote administration tool with potential for malicious misuse. If installed by a hacker, it has the ability to give a remote attacker full system administrator privileges to your system. It can also 'sniff' passwords and confidential data and quietly e-mail them to a remote site. Back Orifice is an extensible program; programmers can change and enhance it over time.

BACK PLANE:

1) The connector blocks and special wiring at the rear of an equipment cabinet or cabinet shelf: Printed circuit board modules are normally inserted from the front of the back plane or front of the cabinet.

2) The physical connection between an interface processor or card and the data buses and the power distribution buses inside a chassis.

BACK PRESSURE:

Propagation of network information congestion upstream through an inter-network

BACKUP:

A duplicate copy of data made for archiving purposes or for protecting against damage or loss.

Some programs backup data files while maintaining both the current version and the preceding version on disk. However, a backup is not considered secure unless it is separately stored from the original.

BACK UP DOMAIN CONTROLLER:

A server in a network domain that stores and uses a copy of the domain's user accounts database to validate log on requests.

BACKUP/RESTORE:

The act of copying files and databases to protect them in the event of a system failure and then retrieving them at a later date

BACK UP SERVER:

(Shadow Server/Fallback) - Software and/or hardware which maintains a concurrent copy of files so that there are always two current copies of each file.

BACKUP:

In computer systems and communications the term refers to the duplication of hardware and software resources that help recover the system operation following an operational degradation or failure of one or more system components.

BACKWARD CHANNEL:

Same as Asymmetrical Modulation or Reverse Channel; See reverse channel

BACKWARD EXPLICIT CONGESTION NOTIFICATION (BECN):

A bit in the frame relay header indicating the frame has passed through a node experiencing congestion in the opposite direction, from which the referenced frame is traveling. DTE receiving frames with the BECN bit set can request that higher-level protocols take flow control action as appropriate.

BACKWARD INDICATOR BIT:

Part of an SS7 MSU, when toggled, sends a negative acknowledgment from the remote signaling point.

BACKWARD LEARNING:

Algorithmic process used for routing traffic (data) that compiles information by assuming symmetrical network conditions. For example, if node ‘A’ receives a packet from node ‘B’ through an intermediate node ‘C’, the backward-learning routing algorithm assumes that ‘A’ can also send to ‘B’ through ‘C’.

BACKWARD SEQUENCE NUMBER:

A function of the SS7 MSU protocol that acknowledges the receipt of data (signal unit) from a remote signaling (sending) point; contains the sequence number of the data being acknowledged

BAF:

Bellcore AMA Format: A system of abstract syntax and semantics that supports coding of AMA data into records.

BALANCED/UNBALANCED:

A device frequently used to connect IBM 3270-type terminals, which require unbalanced coaxial cable connections to balanced twisted-pair cabling; Device used for matching impedance between a balanced and an unbalanced line, usually twisted-pair and coaxial cable.

BALANCED / BALANCED CIRCUIT:

A network terminated circuit having balanced impedances (between telephone line and network) resulting in a low rate of return loses. Contrast with unbalanced-to-ground.

BALANCED CONFIGURATION:

In HDLC, a point-to-point network configuration with two combined stations.

BALANCED LINE:

A transmission line consisting of two conductors capable of being operated in such a way that the voltages of the two conductors are equal in magnitude and opposite in polarity with respect to ground; also the currents in the two conductors are equal in magnitude and opposite in direction.

BALUN:

See Balanced/unbalanced

BAN:

Billing Account Number

BAND:

A range of frequencies between two defined limits, such as a band of 300Hz to 600Hz in width or 300Hz to 3300Hz in width, etc. Or in Wide Area Telecommunications Service (WATS), one of the five geographic areas defined by the carrier. See Bandwidth

BANDPASS:

Defines the maximum range of frequencies that can pass through a specific communications channel without excessive attenuation or distortion

BANDPASS FILTER:

A circuit designed to allow only frequencies within a specific range to pass. The cutoff frequencies must be finite and nonzero.

BANDSPLIT:

The technique of subdividing a channel (band) into sub-channels

BAND SPLITTER:

A multiplexer (FDM or TDM) that divides a Voice Grade (VG) or wider bandwidth channel into several independent narrow bandwidth channels.

BANDWIDTH (BAND):

The difference expressed in hertz, between the highest and lowest frequencies of a band (group) of frequencies. A measure of the ability of equipment or transmission facilities (lines) to pass a range of electromagnetic frequencies.

BANDWIDTH ALLOCATION / RESERVATION:

The process of assigning the appropriately required bandwidth to users and applications that are served by a network; involves assigning priority to the various traffic processed based on a critical and delay-sensitive criteria. This makes the best use of available bandwidth, and if the network becomes congested, lower-priority traffic can be delayed or dropped.

BANDWIDTH COMPRESSION:

References a technique used to reduce the requirements for channel transmission capacity. Reduces the total frequency range (bandwidth), which allows a higher transmission rate by reducing the channel bandwidth requirement; results in a reduced operational cost.

BANDWIDTH on DEMAND INTEROPERABILITY GROUP (BONDING):

Refers to an industry trade group formed to establish standards for bandwidth on demand services

BANG ADDRESS:

An old system of mail addressing in UUCP networks, where the successive routing addresses were followed by exclamation points (known as bangs) and the addressee was the last element.

BANYAN VINES:

Virtual Integrated Network Service: NOS developed and marketed by Banyan Systems.

BARGE IN:

The interruption of an established connection

BARRNet:

Bay Area Regional Research Network: A regional network serving the San Francisco Bay Area; composed of four University of California campuses.

BAS:

See Bit Rate Allocation Signal

BASE RATE:

The non-discounted charge for measured services

BASE STATION:

A fixed land station (receiver/transmitter ‘relay’) that provides telephone/data service for mobile telephones. See Cells

BASEBAND / BASEBAND TRANSMISSION:

1) A signal transmitted at its original frequency. In modern usage, ‘Base Band’ refers to a transmission system where the signal uses up all of a channel's bandwidth.

2) May refer to a network technology where only one carrier frequency is used; may also be called a narrowband facility. Ethernet is an example of a base-band network.

BASEBAND MODEM:

Line Driver, Data Set or some type of Data Communications Equipment (DCE)

BASEBAND SIGNALING:

References the un-modulated transmission of signals at their original frequencies

BASE GROUP:

A channel bandwidth capable of handling twelve Voice Grade (VG) channels: Could be divided through the use of Frequency Division Multiplexing (FDM).

BASELINE:

Establishing a point of reference

BASH:

Bourne-Again Shell: An interactive UNIX shell based on the traditional Bourne shell, but with increased functionality.

BASIC (Programming Language):

Beginner’s All-purpose Symbolic Instruction Code: A programming instruction code with many English like terms (words).

BASIC DISK:

A physical disk that can be accessed by MS-DOS and all Windows-based operating systems: Basic disks can contain up to four primary partitions, or three primary partitions and an extended partition with multiple logical drives.

BASIC ENCODING RULES:

Rules for encoding data units described in the ISO ASN.1 standard. May refer to Bit Error Rate: The ratio of received bits that contain errors;

BASIC INPUT/OUTPUT SYSTEM (BIOS):

On x86-based computers, the set of essential software routines that test hardware at startup, start the operating system, and support the transfer of data among hardware devices. The BIOS is stored in read-only memory (ROM) so that it can be executed when the computer is turned on. Although critical to performance, BIOS is usually invisible to computer users.

BASIC RATE ACCESS (BRA):

BRA provides Integrated Services Digital Network (ISDN) users access to two 64Kbps data channels, as defined in International Telecommunications Union (ITU-TS) Recommendation I.420 which covers a 2B + D channel where the B channel is a 64Kbps channel, and the D-channel is a 16Kbps signaling channel.

BASIC RATE INTERFACE:

Three digital signals over a single pair of copper wires; voice and fax on a single pair of wires or two voice (B) channels and one signaling (D) channel; ISDN interface composed of two B channels and one D channel for circuit-switched communication of voice, video, and data

BASIC STORAGE:

A storage method in MS-DOS, Windows, Windows NT, and Windows 2000 for primary partitions, extended partitions and logical drives

BASIC TELECOMMUNICATIONS ACCESS METHOD:

See BTAM

BASIC VOLUME:

A primary partition or logical drive that resides on a basic disk

BATCH FILE TRANSFER:

The transmission of more than one file at a time by a file transfer protocol.

BATCH FILES:

Text files containing one MS-DOS command on each line of the file. When run, each line executes in sequential order. The batch file AUTOEXEC.BAT is executed when the computer is booted and loads a series of controls and programs. This file type has the extension BAT.

BATCH PROGRAM:

An ASCII (unformatted text) file that contains one or more operating system commands. A batch programs file name has a .cmd or .bat extension. When you type the file name at the command prompt, or when the batch program is run from another program, its commands are processed sequentially. Batch programs are also called batch files.

BATCH ORIENTED:

A processing system that groups input data into subsets and processes them periodically rather than in real time.

BATCH PROCESSING:

In communications the term refers to a data processing technique where related transactions are grouped together and are sent in one transmission for processing. Or the related transactions may come from different sources.

BAU:

Basic Arithmetic Unit: A unit within the Central Processing Unit (CPU) including display registers, where mathematical calculations are performed.

BAUD:

A data transmission bit rate measurement formula named after Baudot as in the Baudot code. It is the measurement of the shortest signal element transition(s), which is transmitted by the communications media. Technically, baud is the number of times per second that the signal shifts (changes) value. For example a 1200 bit per second MODEM actually operates at 300 baud, but it moves 4 bits per baud (4 x 300= 1200 bits per second).

BAUDOT CODE:

A five bit data communications code set named after the inventor. This code set was the most widely used for message transmission prior to the ASCII code set. A start and stop bit was usually added because of the requirement to start and stop the Teletype machine mechanism. This resulted in a 7 to 7.42 bit code set.

BAY:

Another name for equipment rack, enclosure or cabinet

BAY AREA REGIONAL RESEARCH NETWORK:

See BARRNet

BAYONET NEILL CONCELMAN:

See BNC

BBN

Bolt, Beranek, and Newman, Inc: A company located in Massachusetts that developed and maintained the ARPANET (and later Internet) core gateway system

 BBN PLANET:

A subsidiary company of BBN (Bolt, Beranek, and Newman, Inc) that operates a nationwide Internet access network

BBU:

Bit Buffer Unit: A storage register contained in the ADU; Stores one bit or a designated group of bits, which are then transferred to the Data Memory in the ADU.

BBS:

Bulletin Board System: A computer system that functions as a centralized information source and message board system for a particular group of users.

   A computerized meeting and announcement system that allows people to carry on discussions, upload and download files, and make announcements without the people being connected to the computer at the same time. In the early 1990's there were many thousands BBS around the world, most were very small, running on a single IBM clone PC with 1 or 2 phone lines.

BBU (Battery Backup Unit):

A battery-operated power supply used as an auxiliary source of power in the event of power failure. The battery guarantees no lost information and an orderly transition or shutdown during power outages.

BC(c):

Committed Burst: Negotiated tariff metric in Frame Relay inter-networks; the maximum amount of data (in bits) that a Frame Relay inter-network is committed to accept and transmit at the CIR.

BCC:

Block Check Character: A character added to a block of transmitted data for error detection purposes. In longitudinal redundancy checking and cyclic redundancy checking, block check characters are computed for, and added to, each message block transmitted. This block check character is compared with a block check character computed by the receiver to determine whether the transmission is error free.

BCD:

Binary Coded Decimal: The representation of a decimal number by no fewer than four binary digits.

BCE Inc.:

Canada's largest telecommunications company

BCP: 

Best Current Practices: The newest sub-series of RFC(s) that are written to describe BCP(s) in the Internet. Rather than specifying a protocol, these documents specify the best ways to use the protocols and the best ways to configure options to ensure interoperability between various vendors' products.

BDCS:

Broadband Digital Cross-Connect System: SONET DCS capable of cross-connecting DS-3, STS-1 and STS-3c signals.

BECN:

See Backward Explicit Congestion Notification

BCH CODE:

Bose-Chaudhuri-Hochquengham Code: A multilevel, cyclic, error-correcting, variable-length digital code used to correct data transmission errors. BCH codes are not limited to binary codes, but may be used with multilevel phase shift keying under certain conditions.

BCI:

Bit Count Integrity

BCU:

Buffer Control Unit: A hardware control unit that controls the transfer of bits to and from the BBU (Bit Buffer Unit), based on control signals from the ADU.

BCV:

Business Continuance Volumes: Business Continuance Volumes are copies of active production volumes that can be used to run simultaneous tasks in parallel with one another. This gives users the ability to do concurrent operations, such as data warehouse loads and refreshes or point-in-time backups, without affecting production systems.

Bd:

Baud

BE(e):

Excess Burst: Negotiated tariff metric in Frame Relay inter-networks. The number of bits that a Frame Relay inter-network attempts to transmit after Bc (Committed Burst) is accommodated. Be data, in general, is delivered with a lower probability than Bc data because Be data can be marked as DE (Discard Eligible) by the network.

BEACON:

Refers to a condition where no data can pass on a Token Ring or Fiber Distributed Data Interface (FDDI) network; frame from a Token Ring or FDDI device indicating a serious problem with the ring, such as a broken cable. A beacon frame contains the address of the station assumed to be down.

BEACON FRAME:

A special purpose frame used (sent) in token passing networks to indicate and recover from a break in the ring.

BEACONING:

A Token Ring process used to recover the network when any attached station has sensed that the ring is inoperable because of a hard error. A station detecting a ring failure upstream transmits (beacons), a special Media Access Control (MAC) frame, using beacon transmit and beacon repeat modes that isolates the location of the error.

BEARER CHANNEL:

A DS0 time slot that carries analog voice or digital data over ISDN; a full-duplex, 64-kbps channel used to send user data

BECAUSE IT’S TIME NETWORK:

A low-cost, low-speed academic network consisting primarily of IBM mainframes and 9600-bps leased lines.

BECN:

Backward Explicit Congestion Notification: A bit set by a Frame Relay network in frames traveling in the opposite direction of frames encountering a congested path. DTE receiving frames with the BECN bit set can request that higher-level protocols take flow control action as appropriate.

BEL (Bell):

A special Baudot Character or an ASCII control character: Causes a bell to ring (single ding) on the receiving device.

BELL 103 MODEM:

An AT&T MODEM that provides asynchronous originate/answer operations, at speeds up to 300 bps.

BELL 113 MODEM:

An AT&T MODEM that provides asynchronous operation with either originate or answer capability (not both) at speeds up to 300 bps.

BELL 201 MODEM:

An AT&T MODEM that provides synchronous operation at 2400 bps.

BELL 202 MODEM:

An AT&T MODEM that provides asynchronous operation at 1800 bps, on a four-wire circuit, with full-duplex operation. Also refers to an AT&T asynchronous 1200 bps MODEM using a two-wire, full-duplex, circuit.

BELL 208 MODEM:

An AT&T MODEM that provides synchronous operation at 4800 bps. 208A is used for leased lines and 208B for public telephone networks.

BELL 209 MODEM:

An AT&T MODEM that provides synchronous operation, on four-wire circuits (lines) at 9600 bps

BELL 212/212A MODEM:

An AT&T MODEM that provides asynchronous, full-duplex, 300 and 1200 bps operation.

BELL 43401:

A bell publication defining the requirements for data transmission over limited distance continuous private metallic circuits (DC) supplied by the regional telephone company.

BELL CANADA:

Canada's largest supplier of telecommunications services

BELL COMMUNICATIONS RESEARCH (Bellcore):

A research organization jointly owned by the seven (original number) Regional Bell Holding Companies (RBHC). Bellcore conducts research, establishes industry standards, and provides technical resources and management services to the holding companies.

BELLCORE:

See Bell Communications Research

BELLMAN-FORD ROUTING ALGORITHM:

A group of routing algorithms that determine the number of hops required in a route to find the shortest-path spanning tree. Distance vector routing algorithms call for each router to send its entire routing table in each update to its neighbors.

BEMS:

See Business Exchange Measured Service

BENCHMARK (BM):

A device or task measuring standard or expected result

BER:

Bit Error Rate (Bit Error Ratio): A measure of quality in digital transmission systems; expresses the ratio of correct bits to erroneous bits.

BERKELY INTERNET NAME DOMAIN (BIND):

Refers to DNS developed and distributed by the University of California at Berkeley (United States). Many Internet hosts run BIND, which is the ancestor of many commercial BIND implementations.

BERKELEY SOFTWARE DISTRIBUTION SOCKETS (BSD):

A part of layer five in the Open system Interconnection (OSI model

BERKELEY STANDARD DISTRIBUTION (BSD):

A term used to describe any of a variety of UNIX-type operating systems based on the UC Berkeley BSD operating system.

BERT:

Bit Error Ratio (Rate) Test: A test that provides the ratio of bit errors to the total number of bits transmitted; usually shown in exponential form to indicate that one out of a pre-defined number of bits is in error.
BETA TEST:

A secondary product test performed, before general release, by a selected group of end users or customers.

BEST-EFFORT DELIVERY:

Refers to a network system that does not use a sophisticated acknowledgment system to guarantee reliable delivery of information

BGP:

Border Gateway Protocol: Inter-domain routing protocol that replaces EGP. BGP exchanges information with other BGP systems. It is defined by RFC 1163.

BGP4

Border Gateway Protocol Version 4; Version 4 is one of the predominant inter-domain routing protocols used on the Internet. BGP4 supports CIDR and uses route aggregation mechanisms to reduce the size of routing tables.

BH:

See Busy Hour

BIA:

Burned-in MAC Address

BIAS:

A systematic deviation of a value from a reference value: In binary signaling, data communications, bias is a distortion of the signal (bit pattern) where all the significant intervals have uniformly longer or shorter duration (shifted in position), which is a deviation from the original transmitted duration (bit form).

BIB:

Part of an SS7 MSU that when toggled signals (returns) a negative acknowledgment from the remote signaling point.

BIC:

Broadband Inter-Carrier: The International Telecommunication Union Telecommunication Standardization Sector (ITU-T) standard that defines the protocols and procedures needed for establishing, maintaining, and terminating broadband switched virtual connections between public networks.

BICI:

Broadband Inter-Carrier Interface: ITU-T standard that defines the protocols and procedures needed for establishing, maintaining, and terminating broadband switched virtual connections between public networks.

BiCMOS:

See Bipolar and Complementary Metal Oxide Semiconductor

BIDIRECTIONAL PIM / BIDIR-PIM:

Protocol Independent Multicast: A variant of the suite of routing protocols for IP multicast. In PIM, packet traffic for a multicast group is routed according to the rules of the mode configured for that multicast group.

BIGA:

Bus Interface Gate Array: Technology that allows the Catalyst 5000 to receive and transmit frames from its packet-switching memory to its MAC local buffer memory without the intervention of the host processor.

BIG-ENDIAN:

Refers to a method of storing or transmitting data in which the most significant bit or byte is presented first.

BIMODAL VIRUS:

Bimodal (Bipartite) virus infects both boot records and files.

BINARY:

A numbering system based on 2: 0 = absence of a bit or 1 = presence of a bit. A binary bit has two possible states, 1 or 0, marking or spacing, current or no current, etc.

BINARY CODED DECIMAL:

See BCD

BINARY CODED ALTERNATE MARK INVERSION (AMI):

A type of Line-code used on T1 and E1 circuits. In AMI, zeros are represented by 01 during each bit cell, and ones are represented by 11 or 00, alternately, during each bit cell. AMI requires that the sending device maintain ones density. Ones density is not maintained independently of the data stream.

BINARY 8-ZERO SUBSTITUTION:

A type of Line code used on T1 and E1 circuits, in which a special code is substituted whenever eight consecutive zeros are sent over the link. This code is then interpreted at the remote end of the connection.

BINARY FILES:

Binary files are files that include up to 256 different characters and are encoded by 8 binary bits for each character. Simple text or ASCII files only use 128 different characters and can be encoded by 7 binary digits. Examples of binary files are most programs, word- processed files, graphics files, and sound files.

BINARY EXPONENTIAL BACK-OFF:

A Local Area Network (LAN) algorithm used to reschedule transmissions after a collision.

BINARY LARGE OBJECT (BLOB):

The movement of massive image files through Local Area Networks (LAN).

BINARY PHASE SHIFT KEYING:

See Phase Shift Keying (PSK)

BINARY SIGNALING:

Information represented by the presence or absence of ones or zeros or positive or negative (plus or minus) voltage variations, with this representation transmitted in a continuous stream, coded as necessary into usable information.

BINARY STREAM:

A serial flow of binary bits, 1's and 0's arranged in accordance with the device(s) code set.

BINARY SYNCHRONOUS PROTOCOL (Bisync, BSC):

An IBM line control procedure: Became an industry standard for data communications. It can utilize several data codes such as 8- bit EBCDIC and 7-bit ASCII and uses a defined set of control characters and sequences for synchronized transmission of data between stations (terminals). See BSC

BINARY SYNCHRONOUS COMMUNICATIONS:

See BSC

BIND:

Berkeley Internet Name Domain: Implementation of DNS developed and distributed by the University of California at Berkeley (United States). Many Internet hosts run BIND, which is the ancestor of many commercial BIND implementations.BINDERY:

Refers to a Novel NetWare Local Area Network (LAN) operating system database that contains definitions for individual users, groups and work-groups; The bindery supports the design, organization and secure operation of the NetWare environment.

BINHEX:

BINary HEXadecimal: A method for converting non-text files (non-ASCII) into ASCII code. This is normally required because Internet e-mail can only handle ASCII code.

BIOS:

Basic Input-Output System: The BIOS code is read (coded) into a PC's ROM to provide the basic instructions for controlling system hardware. The operating system and application programs both directly access BIOS routines to provide better compatibility for input/output devices.  Some makers of add-in boards such as graphics accelerator cards provide their own BIOS modules that  work in conjunction with (or replace) the BIOS on the system's motherboard.

BIP:

Bit Interleaved Parity: In ATM, a method used to monitor errors on a link. A check bit or word is sent in the link overhead for the previous block or frame. Bit errors in the payload then can be detected and reported as maintenance information.

BIPHASE CODING:

A bipolar coding scheme originally developed for use in Ethernet. Clocking information (bit’s’) is embedded into and recovered from the synchronous data bit stream without the need for separate without electronic clocking input (connection).

BIPOLAR:

Electrical characteristic of a circuit with both negative and positive polarity

BIPOLAR AND COMPLEMENTARY METAL OXIDE SEMICONDUCTOR (BiCMOS):

An integrated circuit process technology that combines bipolar and metal transistor types

BIPOLAR CODING:

Refers to a T carrier line coding system that alternates the polarity of each consecutive one bit See Polar Transmission

BIPOLAR DEVICE:

A current-driven electronic device with two opposite polarity poles

BIPOLAR EIGHT ZEROS SUBSTITUTION (B8ZS):

1) A coding format for Digital Service, level 3, (DS-3) lines in which eight consecutive zeros are replaced with a unique signature, either 000+-00-+ if the preceding pulse was positive, or 000-+00+- if the preceding pulse was negative.

 2) Binary 8-Zero Substitution:  Line-code type used on T1 and E1 circuits, in which a special code is substituted whenever eight consecutive zeros are sent over the link. This code then is interpreted at the remote end of the connection. This technique guarantees ones (1’s) density independent of the data stream.

BIPOLAR FIELD EFFECT TRANSISTOR (BIFET):

A linear circuit that combines bipolar and field-effect transistors (FET) on the same chip

BIPOLAR RETURN TO ZERO (BPRZ):

A 3 level code in which alternate one bits change in value (sign): For example, 1011 becomes +1, 0, -1, +1. Also, transitions between adjacent ones pause at the zero voltage level

BIPOLAR TRANSISTOR:

A transistor that uses both negative and positive charge carriers

BIPOLAR THREE ZEROS SUBSTITUTION (B3ZS):

A coding format for Digital Service (DS-1/DS-3) lines that uses Bipolar Violations (BPV) to encode strings of three consecutive zeros. The BPV polarity inserted depends on the preceding pulses

BIPOLAR TRANSMISSION:

A method of sending binary data in which negative and positive states alternate: used in digital transmission facilities.

BIPOLAR VIOLATION (BPV):

A condition which occurs when an Alternate Mark Inversion (AMI) coded signal contains a pulse of the same polarity as the previous pulse, which is not part of a bipolar zero substitution code. Such as, Bipolar Three Zeros Substitution (B3ZS) for a Digital Service level 1 (DS-1) signal or Bipolar Eight Zeros Substitution (B8ZS) for DS-3 signals.

BIPOLAR VIOLATION RATIO:

The number of accumulated Bipolar Violations (BPV) in the last monitored interval divided by the number of bits in that interval: Any one-second where there is a Loss of Signal (LOS) condition will not be included in this computation.

BIPOLAR WITH EIGHT ZERO SUBSTITUTION (B8ZS):

The clear channel line coding option on Digital Service, level 1 (DS-1): Allows the DS-1 user to obtain greater throughput and functionality from their DS-1 facilities. The use of B8ZS allows users to transmit data at a rate of 64 Kbps per DS-0, achieving what is referred to as a clear channel. Using all 24 DS-0s on a DS-1, the effective data throughput of the DS-1 facility is increased with B8ZS from 1.344 Mbps to 1.536 Mbps. Channel Service Units (CSU) with B8ZS support are required on both ends of the circuit.

BIRD:

Another name for a satellite

BIS (bis):

A term added to some Consultative Committee International Telephone and Telegraph (CCITT) network interface standards. It is also used to identify the second version of a specific CCITT standard.

BISDN:

Broadband Integrated Services Digital Network: A packet switching technique that uses packets of fixed length, resulting in lower processing and higher speeds; ITU-T communication standards designed to handle high-bandwidth applications, such as video. BISDN currently uses ATM technology over SONET-based transmission circuits to provide data rates from 155 to 622 Mbps or higher.

BISYNC:

Binary Synchronous Communications 

BIT:

Binary digit: Either a 0 or 1 or no voltage or voltage present, of a predetermined width. See binary. Also see Built in Test

BIT DURATION:

The time it takes for one bit to pass a point on a transmission medium. Bit width measurement.

BIT ERROR COUNT:

Refers to the total number of bit errors counted during a timed interval.

BIT ERROR RATE/ BIT ERROR RATIO (BER):

The ratio of received error bits relative to a specific number of bits received. Also a measure of noise induced distortion in digital communications links. See BER

BIT ERROR RATE TESTER (BERT):

A method or device used to measure the bit transmission quality, which would include, the pattern of bit transmission, and the number of bit errors received. The figures obtained are used to compute the Bit Error Rate (BER).

BIT INTERLEAVING:

A form of Time Division Multiplexing (TDM) for synchronous protocols: Bit inter-leaving retains the sequence and number of bits, so that correct synchronization is maintained.

BIT INTERLEAVED PARITY:

In ATM, a method used to monitor errors on a link. A check bit or word is sent in the link overhead for the previous block or frame. Bit errors in the block then can be detected.

BIT ORIENTED:

A term used to describe a binary system or a communications protocol where the control information is encoded (contained) within one or more bits. Example: IBM Synchronous Data Link Control (SDLC).

BIT-ORIENTED PROTOCOL:

A data transmission protocol that moves a stream of information bits one bit at a time without concern for the bit meaning. A data link layer communication protocol that transmits frames without concern for the frame content; not byte oriented.

BITMAP:

A graphic which is defined by specifying the colors of dots or pixels which make up the picture: Also known as raster graphics. Common types of bitmap graphics are GIF, JPEG, Photoshop, PCX, TIFF, Macintosh Paint, Microsoft Paint, BMP, PNG, FAX formats, and TGA.

BITNET:

‘Because It's Time NETwork’ or ‘Because It's There NETwork’: A network of educational sites separate from the Internet, but e-mail is freely exchanged between BITNET and the Internet. BITNET is probably the only international network that has been shrinking.

BITNET III:

Dial-up service providing connectivity for members of CREN

BIT RATE:

A measurement of the number of bits transmitted over a communications line each second, usually expressed in ‘bits per second’ (bps). Bit rate should not be confused with Baud which defines the rate of signal state changes (transitions).

BIT RATE ALLOCATION SIGNAL (BAS):

In Consultative Committee International Telephone and Telegraph (CCITT) recommendation H.221 and T.120, a word within the frame structure used to transmit commands, control and indication signals/capabilities; H.221, frame structure for audiovisual services and T.120, an International Telecommunications Union (ITU-T) recommendation describing transmission protocols for data, including multilayer protocols.

BIT ROBBING:

A data transmission technique: Allows the digital data in the DS1 stream to carry the signaling and supervision information. The least significant bit per channel in every sixth frame carries the signaling.

BIT STREAM:

The continuous transmission of digital information (bits) on a circuit.

BIT STRIPPING:

Refers to a multiplexer function where bit stripping involves the removal of the start/stop bits on asynchronous transmitted characters and then the data is transmitted synchronously.

BIT STUFFING:

References the insertion of an occasional dummy bit into a binary stream so that the mean data rate is slightly less than the bit signaling (ultimate transfer) rate of the channel. The position of the stuffed bits must be identified on a supplementary channel. Synonyms: pulse stuffing and zero-bit insertion

BITMAP:

Character or graphic representations by individual pixels arranged in rows (horizontal) and columns (vertical). Each pixel can be represented by either one bit (simple black and white) or up to 32 bits (high definition color).

BITNET:

A commercial network representing a gateway to the Internet: This system is an outgrowth of the ARPAnet (Advanced Research Projects Agency Network) system and provides various levels of Internet support for its users. The ARPAnet has been commercialized and merged with networks such as Bitnet.

BITS:

Building Integrated Timing Supply: A clock in a central office that supplies DS1 and/or composite clock timing references to all synchronous network elements in that office.

BLACK HOLE:

Routing term for an area of the inter-network where packets enter, but do not emerge, due to adverse conditions or poor system configuration within the network.

BLANK(S)

A term used to define a condition of no information in data recording medium and usually indicated by the presence of all zeros or all spaces.

BLER:

Block Error Rate: The ratio of the number of blocks transmitted to the number of blocks containing errors.

BLERT:

Block Error Rate Test: Data transmission testing in which the error rate counted is the number of blocks containing errors instead of the actual number of bit errors. Many users claim this is more representative of the real throughput quality of a circuit than simple BER testing.

BLF:

See Busy Lamp Field

BLOB:

See Binary Large Object

BLOCK:

1) A group of bits or digits that is transmitted as a unit and that may be encoded for error control purposes.

2) A string of records, words, or characters that for technical or logical purposes are treated as a unit.

3) A group of characters, bytes or words communicated as a unit, usually framed by control characters.

BLOCK BY BLOCK TRANSMISSION MODE:

A transmission mode in which a line block is not transmitted until proper acknowledgment is received for the preceding line block.

BLOCK CHAINING:

The linking of queued (stored) blocks of data through the use of pointers or flags

LOCK CHECK:

An error control procedure that is used to determine whether a block of data is structured according to given rules (error free).

BLOCK CHECK CHARACTER:

See BRC

BLOCK CODE:

An error detection and/or correction code

BLOCK DIAGRAM:
A diagram of a system, hardware or software, in which the components or portions are represented by annotated boxes and symbols and connecting lines.

BLOCK ERROR:

For Digital Data Service (DDS), indicates one or more bits, during one-second, are in error. For other applications the block size and timing may vary.

BLOCK ERROR RATE:

A ratio of the number of blocks received with errors compared to those received correctly.

BLOCK ERROR RATE TEST / TESTER:

See BLERT

BLOCK FRAMING:

A form of data transmission control: Data is framed into line blocks of 80 data characters with four framing characters, two ahead of the data and two following the data. This makes each line block a total of 84 characters.

BLOCK LENGTH:

The total number of records, words, or characters contained in one (framed) block

BLOCK MULTIPLEXER CHANNEL:

An IBM term used to describe a multiplexer channel that interleaves blocks of data.

This channel also is referred to as OEMI channel and 370 block mux channel.

BLOCK REDUNDANCY CHECK:

See (BRC)

BLOCK SERIAL TUNNEL:

A base station subsystem: Refers to the radio-related functions provided by the BTS and BSC in a GSM mobile wireless network.

BLOCK SIZE:

Could be the same as Block Length, but when this term references either error control or data compression protocols, it refers to the number of characters to be sent at one time. If error control is used, the control codes are sent immediately following the block.

BLOCKING;

Usually refers to a telephone ‘busy signal’, but could also apply to a transmission denial condition in a switching system when circuits are unavailable for connection or to receive data. The term also is used to describe a situation in which one activity cannot begin until another is completed.

BLOG / WEB LOG:

Web LOG: A blog is basically a journal that is available on the web. The activity of updating a blog is ‘blogging’ and someone who keeps a blog is a ‘blogger’. Blogs are typically updated daily using software that allows people with little or no technical background to update and maintain the blog. Postings on a blog are almost always arranged in chronological order with the most recent additions featured most prominently.

BLOGOSPHERE OR BLOGSPHERE:

Represents the current state of all information available on BLOG systems and/or the sub-culture of those who create and use the BLOG systems

BLSR:

Bidirectional Line Switch Ring: SONET ring architecture that provides for multiple fiber cable connections between nodes. If the working fiber cable connection between nodes is cut, traffic is routed automatically onto an alternate fiber cable.

BLUE ALARM:

Same as ‘Alarm Indication Signal (AIS)’ - An unframed one’s (bits) signal that replaces the normal data signal when a maintenance alarm has been activated.

BLUETOOTH:

A short range wireless protocol meant to allow mobile devices to share information and applications without connecting cables; Operates at 2.4 GHz. The name refers to a Viking King who unified Denmark.

BNC:

Bayonet Neill Concelman: A miniature coaxial cable connector that uses a bayonet locking mechanism.

BNC CONNECTOR:

A connector for coaxial cables that locks when one connector is inserted into another and rotated 90 degrees

BNI:

Broadband Network Interface

BNM:

Broadband Network Module

BNN:

Boundary Network Node: In SNA terminology, a sub-area node that provides boundary functional support for adjacent peripheral nodes. This support includes sequencing, pacing, and address translation.

BNR:

Bell Northern Research, Ltd.

BOARD:

In data communication this could reference a printed circuit card or a circuit card that can be altered by adding or deleting external wiring.

BOB:

See Breakout Box

BOC:

Bell Operating Company(s): A term used when discussing one or more of the 22 local telephone companies spun off from AT&T during January 1984, and then they were organized into seven regional Bell holding companies. Subsequent mergers have reduced that number.

BOBI:

Break-Out / Break-In: VNS feature that allows inter-working between Euro-ISDN (ETSI) and other VNS-supported signaling variants, such as DPNSS and QSIG.

Bolt, Beranek, and Newman, Inc.:

A company located in Massachusetts that developed and maintained the ARPANET (later the Internet) gateway system.

BONDING:

Bandwidth on Demand Interoperability Group – Refers to an industry trade group formed to establish standards for bandwidth on demand services.

BONG:

An interactive signal (symbol): Prompts the originating end user to enter additional information. For example: 10555 ‘bong’ (enter destination) ‘bong’ (enter billing information)

BOOLEAN ALGEBRA:

A process of reasoning or deductive system theorems using symbolic logic: Symbols such as AND, OR, NOT, EXCEPT, IF, THEN, etc. are representative operators used for mathematical calculations; Named after George Boole.

BOOT:

The process of starting or resetting a computer: When first turned on (cold boot) or reset (warm boot), the computer runs the software that loads and starts the computer's operating system.

BOOTFLASH:

A separate Flash memory device used primarily to store the Cisco IOS boot helper image, operational Cisco IOS images, and system configuration information

BOOT HELPER:

A minimum-function Cisco IOS image that only boots the full-function, operational Cisco IOS image

BOOTP:

Bootstrap Protocol: The protocol used by a network node to determine the IP address of its Ethernet interfaces to affect network booting.

BOOT PARTITION:

The partition that contains the Windows operating system and its support files. The boot partition can be, but does not have to be, the same as the system partition.

BOOT PROM / BOOT PROGRAMMABLE READ-ONLY MEMORY:

A chip mounted on a printed circuit board used to provide executable boot instructions to a computer device.

BOOT RECORD:

The program recorded in the boot sector. This record contains information on the characteristics and contents of the disk and information needed to boot the computer. If a user boots a PC with a floppy disk, the system reads the boot record from that disk.

BOOT SECTOR:

An area located on the first track of floppy disks and logical disks that contain the boot record. Boot sector usually refers to this specific sector of a floppy disk, whereas the term Master Boot Sector usually refers to the same section of a hard disk.

BOOT SECTOR INFECTOR:

A boot sector infector virus places its starting code in the boot sector. When the computer tries to read and execute the program in the boot sector, the virus goes into memory where it can gain control over basic computer operations. From memory, a boot sector infector can spread to other drives (floppy, network, etc.) on the system. Once the virus is running, it usually executes the normal boot pair.

BOOT VOLUME:

The volume that contains the Windows operating system and its support files. The boot volume can be, but does not have to be, the same as the system volume.

BOOTING:

‘Bootstrap Loader’: A beginning action following a system failure or loading a computer memory with information needed for it to operate. Remote booting refers to loading (booting) software over the network or from an external source.

BOOTSTRAP LOADER:

A computer input routine, which provides preset operational conditions that enable it to get into an operational mode, following a reset, or failed condition. In personal computers it is the sequence that searches predetermined disks for a Command Interpreter program, then a Configure System file; finally an Auto-execution Batch file.

BOOTSTRAP PROTOCOL:

The protocol used by a network node to determine the IP address of its Ethernet interfaces for network booting.

BORDER GATEWAY:

A router that communicates with routers in other autonomous systems;

An Interdomain routing protocol that replaces EGP; BGP exchanges information with other BGP systems. It is defined by RFC 1163.

BORDER NODE:

A Node in one zone that connects with one or more nodes in other zones

BOT:

Robot: A program designed to search the Internet looking for information. A common use of bots is the variously named spiders, worms, and crawlers that support search engines by following links from site to site and within a site to find information to be indexed by the search engine.

BOTTLENECK:

Refers to the weakest or slowest link in a communication chain, which is commonly the reason for a slow down in message flow.

BOUNDARY FUNCTIONS:

Capability of SNA sub-area nodes to provide protocol support for attached peripheral nodes. Typically found in IBM 3745 devices.

BOUNDARY NODE / BOUNDRARY NETWORK NODE:

In IBM System Network Architecture (SNA) terminology, this would be a sub area node that can provide some protocol support for adjacent sub area nodes. This support includes sequencing, pacing, and address translation.

BOUNDARY ROUTING:

Refers to a 3Com proprietary name for a form of bridging, which allows access to remote networked locations, such as a bank branch office; basically a way to reduce the need for local technical expertise and expensive equipment at the remote site and provide communications management from the head office.

BP:

Block Parity or Bypass

BPDU:

Bridge Protocol Data Unit: Spanning-Tree Protocol hello packet that is sent out at configurable intervals to exchange information among bridges in the network.

BPI:

1) Bits per Inch: Normally used to specify packing density, such as when specifying tape density for magnetic tape devices; synonymous with characters per inch.

2) Baseline Privacy Interface

BPRZ:

See Bipolar Return to Zero

Bps:

See BPS (Bytes Per Second)

bps:

Bits per Second (binary digits): Replaced BAUD for unit of transmission rate measurement (see BAUD). bps/BPS, kbs/KBS, mbs/MBS, etc. The lower-case ‘b’ usually refers to the term bit, where the upper case ‘B’ usually refers to the term ‘Byte’.

BPS:

Bytes per Second: A byte could be a 7 or 8 bit character in the ASCII code or an eight-bit code unit used in computer operations. When the terms bps/BPS, kbs/KBS, mbs/MBS, etc. are used, the lower-case ‘b’ usually refers to the term ‘bit’, where the upper-case ‘B’ usually refers to the term ‘Byte’.

BPU:

Basic Processing Unit: Mainframe part of a computer system housing the arithmetic and data processing functions. May be viewed as having less capability than a Central Processing Unit (CPU) or may be a part of a CPU.

BPV:

Bipolar Violation: A one (1) in a bipolar signal that has the same polarity as the preceding one

See Bipolar Violation

BPV Code:

Bipolar Violation Code: A specific BPV sequence: Introduced into the local loop for network control.

BPV Count:

Bipolar Violation Count: The total number of BPV occurrences counted during a timed test interval.

BPV Rate:

Bipolar Violation Rate: The rate of erroneous received data bits compared to total received data bits. This rate excludes framing bits, CRC-6 bits, or data link bits.

BPX SERVICE NODE:

Closely integrated BPX switch, AXIS interface shelf, and extended services processor designed to support ATM and Frame Relay switched virtual circuits, as well as traditional PVC(s).

BRA:

Basic Rate Access: Two 64 kbps B channels + one 16 kbps D channel (2B + D), carrying user traffic and signaling information respectively to the user via twisted pair local loop.

See Basic Rate Access

BRANCH SYSTEMS GENERAL LICENSE (BSGL):

A license that must be obtained by any organization seeking to link its own private network to the Public Switched Telephone Network (PSTN)

BRC:

Block Redundancy Check: The information added to a transmitted block of data to verify the accuracy of data before it is accepted. The sender of the data block inserts predefined block check information and the receiver performs calculations on the received data, and compares the received block check information. The block is accepted only if the comparison is exact. Synonym: block check character(s)

BREAK:

The momentary interruption of data transmission; This term has different usage, but one example would be a spacing condition, longer than 110 milliseconds, used as a signal to interrupt (break-in) a busy circuit. Normally this feature is used with Teletype, half duplex circuits.

BREAK-OUT / BREAK-IN:

A VNS feature that allows inter-working between Euro-ISDN (ETSI) and other VNS-supported signaling variants, such as DPNSS and QSIG.

BREAKOUT BOX (BOB):

Electronic Industries Association (EIA) Monitor - A breakout box is used to monitor the status of RS-232C signals via a tap on the pins of the RS-232C connector or cable. This monitor also allows signals to be broken, patched, or cross - connected.

BREAKOUT PANEL:

A component part of a larger cabinet or device

BREW (Binary Runtime Environment for Wireless): 

A QUALCOMM programming platform designed to facilitate the development and use of data applications that can function on any CDMA (Code Division Multiple Access) based wireless device. Common applications include games and software for corporate functions. See J2ME for a similar technology from Sun Microsystems.

BRF:

Bridge Relay Function

BRHR:

Basic Research and Human Resources: Component of the HPCC program designed to support research, training, and education in computer science, computer engineering, and computational science.

BRI:

Basic Rate Interface: This is an Integrated Services Digital Network (ISDN) interface typically used by smaller sites and customers. This interface consists of a single 16 Kbps Data channel (D) plus 2 Bearer channels (B) for voice and/or data; also known as Basic Rate Access (BRA).
BRIDGE:

Hardware and software used to connect networks. It is normally used in connecting LANs of identical communication method, medium, and topology. After connection with a bridge, the LANs may form a larger LAN or WAN if dial-up lines are used. Bridges operate at the data link layer (Layer 2) of the OSI reference model. In general, a bridge filters, forwards, or floods an incoming frame based on the MAC address of that frame.

BRIDGE FILTERS:

A method of isolating bridged telephone pairs by using relays or inductors.

BRIDGE FORWARDING:

A process that uses entries in a filtering database to determine whether frames with a given MAC destination address can be forwarded to a given port or ports.

BRIDGE GROUP:

A bridging feature that assigns network interfaces to a particular spanning-tree group. Bridge groups can be compatible with the IEEE 802.1 or the DEC specification; a group of interfaces bridged together to emulate a multi-port bridge.

BRIDGE GROUP VIRTUAL INTERFACE:

Logical Layer 3-only interface associated with a bridge group when IRB is configured.

BRIDGE NUMBER:

A number that identifies each bridge in an SRB LAN; parallel bridges must have different bridge numbers.

BRIDGE PROTOCOL DATA UNIT:

Refers to a Spanning-Tree Protocol hello packet that is sent out at intervals in order to exchange information among bridges in the network

BRIDGE STATIC FILTERING:

Refers to the process in which a bridge maintains a filtering database consisting of static entries. Each static entry equates a MAC destination address with a port that can receive frames with this MAC destination address and a set of ports on which the frames can be transmitted; defined in the IEEE 802.1 standard.

BRIDGE TAP:

A connection of a 2nd local loop to a primary local loop: Generally it behaves as an open circuit with DC, which can become a transmission line stub with adverse effects at high frequency. It is generally harmful to DSL connections and should be removed. Extra telephone wiring (connections) within a home is a combination of short bridge taps. A POTS splitter isolates the house wiring and provides a direct path for the DSL signal to pass unimpaired to the ATU-R MODEM.

BRIDGE UNIT:

In telecommunications networks, a bridge connects a Local Area Network (LAN) to another LAN that uses the same protocol (I.E. Ethernet or Token Ring). A bridge examines each message on a LAN and ‘retains’ those to be routed within the same LAN, and forwards those to be routed to the other interconnected LAN(s).

BRIDGE VIRTUAL INTERFACE (Bridge Group Virtual Interface):

Logical Layer 3-only interface associated with a bridge group when IRB is configured.

BRIDGED CALL:

A feature that allows a station (user) to join an ongoing conversation by entering the proper command code; the requesting station becomes an extension on the line.

BRIDGING (BRIDGE) CONNECTION:

A parallel (hardware) connection on a circuit (line), such as in a multi-point or network circuit, that draws some of the signal energy from the circuit, but has very little effect on the circuit's operation. A combination of hardware and software may be used when connecting to networks; see Bridge.

BRIDGING, ELECTRICAL:

The formation of a conductive path between conductors caused by misalignment, screening, solder splash, smears, or foreign material.

BROADBAND:

A channel facility (line) having a bandwidth greater than a nominal voice grade facility (4000 Hz). In a LAN this may be an analog physical transmission medium of very wide bandwidth, typically 300 megahertz or greater. The term may refer to facilities or services that operate at the DS3 rate and above. For example, a Broadband DCS makes cross-connections at the DS3, STS-1, and STS-Nc levels. Similarly, Broadband ISDN provides about 150 Mb/s per channel of usable bandwidth.

BROADBAND CHANNEL:

Normally refers to a channel with a bandwidth (total frequency) capacity equal to or greater than twelve voice grade channels (approximately 48 KHz plus). Broadband may be divided into multiple frequency channels, operating independently of each other, that can carry voice, data, and video, which is usually achieved through the use of Frequency Division Multiplexing (FDM). Broadband channels are used for high-speed voice and data communications, radio and television broadcasting, some Local Area Networks (LANs), and many other communications applications; see Broadband.

BROADBAND CONNECTION:

A high-speed connection: Broadband connections are typically 256 kilobytes per second (KBps) or faster. Broadband includes DSL (Digital Subscriber Line) and cable MODEM service.

BROADBAND COMMUNICATIONS:

A communications technology that requires high levels of transmission capacity or bandwidth

BROADBAND INTEGRATED SERVICES DIGITAL NETWORK (BISDN):

A packet switching technique that uses packets of fixed length, resulting in lower processing and higher speeds.

BROADBAND INTER-CARRIER INTERFACE:

BICI: International Telecommunication Union Telecommunication Standardization Sector (ITU-T) standard that defines the protocols and procedures for establishing, maintaining, and terminating broadband switched virtual connections between public networks.

BROADBAND ISDN:

BISDN: The ITU-T communication standards designed to handle high-bandwidth applications, such as video. BISDN currently uses ATM technology over SONET-based transmission circuits to provide data rates from 155 to 622 Mbps and higher.

BROADBAND SWITCH MODULE:

ATM port card for the Cisco BPX switch

BROADBAND NETWORK:

A network capable of transmitting voice, data and interactive full-motion video: A broadband network is capable of transmitting a minimum of 1.5 million pieces of information (bits) per second.

 BROADCAST:

A process of sending a message to all possible recipients; broadcasts are identified by a broadcast address.

BROADCAST or TERMINAL BROADCAST:

A term used for a message transmission to all terminals and/or points on a circuit(s) simultaneously, rather than being routed to a specific station. In a Local Area Network (LAN), bus topology, this may refer to a procedure of sending all messages to all stations despite specific terminal addressing.

BROADCAST ADDRESS:

A special address reserved for sending a message to all stations. Generally, a broadcast address is a MAC destination address of all ones.

BROADCAST AND UNKNOWN SERVER:

A multicast server used in ELAN(s) that is used to flood traffic addressed to an unknown destination and to forward multicast and broadcast traffic to the appropriate clients.

BR0ADCAST DOMAIN:

A set of all devices that receive broadcast frames originating from any device within the set. Broadcast domains typically are bound by routers because routers do not forward broadcast frames.

BROADCAST SEARCH:

The propagation of a search request to all network nodes when the location of a resource is unknown to the requester

BROADCAST STORM:

Refers to an undesirable network event in which many broadcasts are sent simultaneously across all network segments. A broadcast storm uses substantial network bandwidth and usually causes network time-outs.

BROM:

Bipolar Read Only Memory: A read only memory module

BROUTER:

A device that combines the routing capability of an Internet router with a bridge that connects to local area networks. A combination of ‘bridge’ and ‘router’; refers to devices that perform both bridging and routing functions.

BROWSER:

Software that interprets files in HTML (Hypertext Markup Language) and formats them into Web pages, and displays them on the monitor screen. Some browsers also permit users to send and receive e-mail, read newsgroups, and play sound or video files embedded in Web documents.

BRUTE FORCE ATTACK:

An attack in which each possible key or password is attempted until the correct one is found

BSC:

1) Binary Synchronous Communication: A continuous stream of data transmitted without start & stop bits. Synchronous control characters (bits/bytes) are inserted in the data stream (flow) at predetermined intervals during the transmission. This allows the transmitting device and receiving device to stay synchronized and maintain controlled and accurate data transfers.

2) Base Station Controller: In wireless, provides the control functions and physical links between the MSC and BTS in a GSM mobile wireless network. The BSC controls the interface between the SGSN and the BTS in a GPRS network. The BSC is a high-capacity telephony switch that provides hands-off functions and cell configuration data, and controls radio frequency power levels in BTS(s). The combined functions of the BSC and the BTS are referred to as the BSS.

BSD:

See Berkeley Software distribution sockets

BSGL:

See Branch Systems General License

BSI:

See: Boot Sector Infector

BSN:

Refers to the part of the SS7 MSU that acknowledges the receipt of signal units (data) from the remote signaling point; contains the sequence number of the signal unit being acknowledged

BSSA/B:

Bulk storage unit, similar to a file server: They replaced the MHD'S Hitachi drives. See MHD.

BSS:

Definitions of BSS relative to Web (Internet) usage:

1) Base Station System; 2) Broadband Switching System; 3) Block storage segment; this is the memory mapping section containing the data allocated for a binary image at execution time; 4) Broadcasting  (Broadcast) Satellite Service: Typically used to refer to a range of frequencies intended for direct reception of satellite television and entertainment services. These frequencies are subject to internationally-agreed regulations that govern their use and are designed to ensure that all countries are able to offer services of this nature. In Europe, the BSS downlink frequency range is 11.7 - 12.5 GHz; 5) Base Station Subsystem: Consists of BSC (Binary Synchronous Communication) and BTS(s) Base Transceiver System; a grouping of network parts that includes the BSC and the BTS (the tower). 6) Basic Service Set: A basic configuration of a wireless LAN (Local Area Network) prescribed by the IEEE 802.11 standard, comprising an AP (Access Point) and at least one wireless node and all communications to and from the wireless node flow through the AP. 7) Backing Storage System: A set of methods included in an API to enable managed objects to be written to and read from a database. 8) Back-Office Support Systems.

BSTUN:

Block Serial Tunnel.

BT:

Burst Tolerance: A parameter defined by the ATM Forum for ATM traffic management. For VBR connections, BT determines the size of the maximum burst of contiguous cells that can be transmitted. Also see Busy Tone

BTA:

Basic Trading Area: A geographic region defined by a group of counties that surround a city, which is the area's basic trading center. The boundaries of each BTA were formulated by Rand McNally & Co. and are used by the FCC (Federal Communications Commission) to determine service areas for PCS (Personal Communication Services) wireless licenses. The entire US and some of its territories is divided into 493 non-overlapping BTAs.

BTAM:

Basic Telecommunications Access Method: A communications access method that supports read/write communications between remote devices.

BTS:

1) Base Transceiver Station: In mobile communications, a BTS holds the radio transceivers that define a cell and coordinates the radio-link protocols with the mobile device. The BTS is the networking component of a mobile communications system from which all signals are sent and received. A BTS is controlled by a Base Station Controller. A BSC controls one or more BTS(s). The combined functions of the BTS and the BSC are referred to as the BSS.

(2) A BTS is also called a Base Station (BS) and is commonly referred to as a ‘cell phone tower’.

BTW:

By The Way: A shorthand indicator appended to a comment written in an online forum.

B2B:

Business to Business: A mode of conducting business between two or more companies over the Internet, rather than more traditional modes such as telephone, mail, and face to face.

B2C:

Business to Consumer: Another business model over the Internet.

B2R:

Back to Reality!

BUFFER (BUFFER STORAGE):

1) Any device or unit, which stores information temporarily during data transfers.

2) A synchronized storage unit between two different forms of storage, usually between internal and external devices.

3) An input unit in which information is assembled from external or secondary storage and stored ready for transfer to internal storage.

4) An output unit into which information is copied from internal storage and held for transfer to secondary or external storage.

5) Buffers are used in internetworking to compensate for differences in processing speed between network devices. Bursts of data can be stored in buffers until they can be handled by slower processing devices. Also may be referred to as a Packet buffer.

BUFFERING:

The process of storing data (bits/characters) to compensate for incompatible device transfer rates. This is usually accomplished in a memory storage device or area, and error checks and re-transmission may be performed as necessary,

BUG:

1) A software or hardware problem (mistake or a malfunction): An unintentional fault in a program that causes actions neither the user nor the program author intended.

2) If one goes back in history to the Morse code days, this would be a high-speed sending key, as in Key and Sounder.

BUILD: To create program or data files for use by the signaling controller database

BUILDING INDUSTRIES CONSULTING SERVICE INTERNATIONAL:

A non-profit association involved in voice or data cable plant design and installation. Also performs an administration function for the Registered Communications Distribution Designer (RCDD) and Local Area Network (LAN) Specialist certifications, and provides related training.

BUILDING INTEGRATED TIMING SUPPLY:

An electronic clock in a central office that supplies DS1 and/or composite clock timing references to all synchronous network elements in that office.

BUILT IN TEST (BIT):

Circuits included in operational equipment expressly for the purpose of providing on-line automatic testing.

BULLETIN BOARD SYSTEM (BBS):

An information gathering computer system that functions as a centralized information source and message system for a group of users

BULK ENCRYPTION:

The process of encrypting two or more telecommunications channels through the use of one piece of encryption equipment.

BURROUGHS DATA LINK CONTROL (BDLC):

Burroughs' proprietary bit-oriented protocol similar to IBM's SDLC

BURST:

1) A data communications event that involves a number of elements, such as in a burst of errors.

2) In other communications areas, a term descriptive of the intermittent occurrence of errors.

3) A sequence of signals (bits) counted as one unit in accordance with some specific criterion or measure.

BURST MODE:

The transmission of bulk data in large continuous blocks over a channel (circuit)

BURST TOLERANCE:

A parameter defined by the ATM Forum for ATM traffic management. For VBR connections, BT determines the size of the maximum burst of contiguous cells that can be transmitted.

BURST TRAFFIC:

Data that is transmitted in bursts instead of continuously.

BURSTY:

Communications characterized by high volumes of data transmitted intermittently, as opposed to steady-stream data transmission.

BUS:

1) One or more conductors or optical fibers that serve as a common connection for a group of related devices.

2) A circuit over which information or power is transmitted.

3) Internally, within the computer, acts as a common connection between devices.

4) In a LAN environment, such as Ethernet, where all network nodes ‘listen’ to all transmissions. Contrast with ring and star. See CSMA/CD.

BUS AND TAG CHANNEL:

IBM channel, developed in the 1960s, incorporating copper multi-wire technology; later replaced by the ESCON channel

BUS BAR:

A heavy copper or aluminum strip or bar used to carry large amounts of current / voltage; or could be used for a ground termination. The bar may provide for the termination of one or more connected wires.

BUS-BASED NETWORK:

A communication network in which all processors are connected by means of a global shared bus

BUS INTERFACE GATE ARRAY:

A technology that allows the Catalyst 5000 to receive and transmit frames from its packet-switching memory to its MAC local buffer memory without the intervention of the host processor.

BUS TOPOLOGY:

‘Linear network topology’ – In a Local Area Network (LAN) bus network all workstations are connected to a single cable and all workstations receive all transmissions on the cable. Each workstation selects those transmissions addressed to it based on the address information contained in the transmission. A bus network is the simplest and most common LAN topology. See Bus.

BUSINESS CONTINUANCE:

The technique of ensuring that a business is able to maintain operational status during a natural or man-made catastrophe by using fault-tolerant and redundant hardware and software systems

BUSINESS EXCHANGE MEASURED SERVICE (BEMS):

A local service usage sensitive rating structure for business in which business customers pay a reduced flat rate for access to the telephone network and a separate per minute charge for their outgoing local calling

BUSINESS MACHINE CLOCKING:

The process of using synchronous clocking signals from the terminal or computer and not from the MODEM

BUSY CONDITION:

Normally refers to a condition where all communications lines or trunks are unavailable for use.

BUSY HOUR or PRIME TIME:

‘Peak Hour’ or ‘Peak Period’ – Refers to a period within a day when the largest number of user transactions occurs.

BUSY LAMP FIELD (BLF):

A peripheral attendant console that enables an operator (attendant) to track the status of all peripherals via a lighted panel or series of lamps; see Console

BUSY TONE (BT):

A single tone that is interrupted at a 60-cycle rate to indicate that the called terminal is busy

BUTT IN:

See Butt Set

BUTT SET:

Refers to a hand carried test telephone used to monitor, dial, and talk on conventional analog telephone lines, so named because a person can clip onto a telephone line and ‘butt in’ on a conversation.

BUTTINSKI:

See Butt Set

BVI:

Bridge Group Virtual Interface: Logical Layer 3-only interface associated with a bridge group when IRB is configured.

BX.25:

AT&T implementation of X.25

BXM:

Broadband Switch Module: ATM port card for the Cisco BPX switch.

BY:

Busy; see Busy Tone

BYPASS (BP):

May refer to an Inter-exchange Carrier (IC) direct connection to user equipment: Example: when an IC connects its own facilities or facilities leased from a non-Bell Operating Company (BOC), directly to an end user's premises. Or the ability of a station or port to be optically or electronically isolated from a ring network while maintaining the integrity of the ring.

BYPASS CIRCUIT/CIRCUITRY:

The restoration of a failed circuit(s) (line) or a device: Restores failed network links and/or equipment.

BYPASS MODE:

The operating mode on FDDI and Token Ring networks in which an interface has been removed from the ring

BYPASS RELAY:

Allows a particular Token Ring interface to be shut down and thus effectively removed from the ring

BYPASS SERVICE:

A Facilities bypass service: Examples: The use of facilities, other than those of the Local Exchange Carrier (LEC), to connect a customer to a Point of Presence (POP) or another customer; the use of operating telephone company private lines to connect a customer to a POP or another customer.

BYTE:

Could be used to identify an eight bit character, or an eight-bit field (word or within a word) used in a computer system. An eight-bit byte could represent.

1) A 7-bit or 8-bit ASCII character.

2) Two 4-bit BCD characters.

3) Two, 4-bit hexadecimal numbers (0 - F).

4) An 8-bit representation of an octal number (0 - 377).

5) One 8 bit binary computer instruction.

6) One 8 bit byte of a multi-byte computer instruction or address.

BYTE MULTIPLEXER CHANNEL:

A computer (mainframe) input/output channel that provides multiplexing or interleaving of data in bytes.

BYTE ORIENTED PROTOCOL:

1) A protocol technique using defined characters (bytes) from a code set for communications control. Compare with bit-oriented protocol. Example: ASCII control characters.

2) A class of data-link communications protocols that use a specific character from the user character set to delimit frames.

BYTE REVERSAL:

The process of storing numeric data with the least-significant byte first; used for integers and addresses on devices with Intel microprocessors.

BYTE STUFFING:

A technique that increases the speed of a digital stream by repeating (duplicating) bytes (characters) and then transmitting them at a faster rate. This technique does not increase the information content of the stream.

BYTES PER SECOND (Bps):

The number of binary bytes transmitted in one second. See BPS