Bachman
Proposed a style of Entity-Relationship modeling which differs from the original Chen proposals.

Back door
A usually hidden or secret means for an external user to break into your host, network, application, or data. See also virus

Backup
A copy of disk files stored on tape or on another physical disk to prevent permanent data loss. The act of copying disk files to tape or other distinct physical media to prevent permanent data loss.

Backup Domain Controller (BDC)
The server that contains a backup copy of the account database from the Primary Domain Controller (PDC). Used for authentication purposes.

Background
Unix can run many programs at the same time. If a program runs behind the scenes, with no interaction with you, it runs in the background.

Back-propagation
An important algorithm for learning in feed-forward networks which makes use of a mathematical trick when the network is simulated on a digital computer, yielding in just two traversals of the network (once forward, and once back) both the difference between the desired and actual output, and the derivatives of this difference with respect to the connection weights.

backslash().
Unix uses a backslash to set off otherwise special characters. In the UNIX shell for example, ƒÄ£ Cû
„Àt< u£Cû
]ÃÌÌÌÌÌÌÌÌÌÌÌÌU‹ìƒìƒ} ery file in the current directory); \ is an actual backslash, if you want one for some reason. DOS users tend to type backslashes by mistake when Unix would rather see a regular slash(/).

backup
A spare copy of your data to keep on the shelf just in case. If you(or a co-worker)delete a file by mistake or if parts of your computer break, you will be inexpressibly happy and smug if you have recently made a backup copy of your important files. Copying files back from your backup is called restoring.

Backus Naur
A formal language for syntax specification.

Backward Explicit Congestion Notification (BECN)
A bit in the Frame Relay header that is set when the network router detects congestion from the source direction (or "backward," from the packet's point of view). See also Forward Explicit Congestion Notification (FECN)

Bamboo
A trusted third-party authentication system from the University of Iowa, similar to Kerberos

Bandwidth
This is a qualitative term used to describe the monitor's Video amplifier potential performance. The higher the pixel rate (or format number), the higher the Bandwidth required of the Video Amplifier.

Bandwidth
In network communication, the amount of data that can be sent across a wire in a given time. Each communication that passes along the wire decreases the amount of available bandwidth.

bang(!)
In Unix-ese, an exclamation point.The C shell command !!, which repeats the last command, for example, is pronounced "Bang!Bang!" Try this with your children they will love it.

Barrel
An outward bowing of the picture.

Baseband
Part of the Bluetooth Protocol stack, enabling the physical radio frequency link between Bluetooth units on a piconet.

Baseline
See Released version

BASIC
Beginners All-purpose Symbolic Instruction Code: a programming language, usually interpreted, suitable for simple applications.

Basic Object Adapter (BOA)
Invokes the performance of a request and returns any results to the client. Also called simply adapter.

Batch Program
An ASCII file that contains one or more Windows NT commands. A batch program’s filename typically has a .bat or .cmd extension. When you type the filename at the command prompt, the commands are processed sequentially.

BAUD
BAUD - A term used to refer to the transmission speed of a modem. The higher the value, the faster the modem. The value is usually measured in Bits Per Second.

BBC
Broadband Bearer Capability: A bearer class field that is part of the initial address message.

BBN
Bolt Beranek and Newman Inc.,of Cambridge, Massachusetts, was awarded the original contract to build the ARPANET and has been extensively involved in Internet development. It is responsible for managing NNSC, CSNET, and NEARnet.

BCC
BCC - "bcc" is an abbreviation for "blind carbon copy," a feature offered by many e-mail programs. When you send a someone a blind carbon copy of a message, his or her name does not appear among the recipients listed in the message's header. As a result, you can send someone a copy of a message without letting its other recipients see that you've done so. To send someone a blind carbon copy, enter his or her address in your e-mail program's bcc: field.

BCD
Binary Coded Decimal: A form of coding of each octet within a cell where each bit has one of two allowable states, 1 or 0.

B-channel
The Integrated Services Digital Network (ISDN) channel that carries voice and user data.

BCOB
Broadband Connection Oriented Bearer: Information in the SETUP message that indicates the type of service requested by the calling user.

BCOB-A
Bearer Class A: Indicated by ATM end user in SETUP message for connection-oriented, constant bit rate service. The network may perform internetworking based on AAL information element (IE).

BCOB-C
Bearer Class C: Indicated by ATM end user in SETUP message for connection-oriented, variable bit rate service. The network may perform internetworking based on AAL information element (IE).

BCOB-X
Bearer Class X: Indicated by ATM end user in SETUP message for ATM transport service where AAL, traffic type and timing requirements are transparent to the network.

BCS
Binary Compatibility Standard: the ABI of 88open

BCS
British Computer Society.

BDC
See Backup Domain Controller (BDC)

BEA
Basic programming Environment for interactive-graphical Applications, from Siemens-Nixdorf.

bearer channel
See B-channel

BECN
See Backward Explicit Congestion Notification (BECN)

BECN
Backward Explicit Congestion Notification: A Resource Management (RM) cell type generated by the network or the destination, indicating congestion or approaching congestion for traffic flowing in the direction opposite that of the BECN cell.

Bedrock
A C++ class library for Macintosh user interface portability.

Benchmark
A standard set of programs which can be run on different platforms to compare performance.

Bento
A multi-vendor initiative allowing files to contain typed parts, to allow standard access between parts of a compound document independent of the file system.

BER
Bit Error Rate: A measure of transmission quality. It is generally shown as a negative exponent, (e.g., 10-7 which means 1 out of 107 bits are in error or 1 out of 10,000,000 bits are in error).

Berkeley Internet Name Daemon (BIND)
An implementation of the DNS protocol. Internet name service software, originally written at the University of California at Berkeley and now maintained by the Internet Software Consortium. Distribution includes /usr/sbin/named and sample configuration files.

Berkeley UNIX
see BSD.

BETA
An object-oriented language and associated programming environment from Mjolner Informatics, Aarhus

BGP
See Border Gateway Protocol (BGP).

BHLI
Broadband High Layer Information: This is a Q.2931 information element that identifies an application (or session layer protocol of an application).

BHT
Budget Holder's Toolkit (at CERN )

Bi
Signaling ID assigned by Exchange B.

B-ICI
B-ISDN Inter-Carrier Interface: An ATM Forum defined specification for the interface between public ATM networks to support user services across multiple public carriers.

B-ICI SAAL
B-ICI Signaling ATM Adaptation Layer: A signaling layer that permits the transfer of connection control signaling and ensures reliable delivery of the protocol message. The SAAL is divided into a Service Specific part and a Common part (AAL5).

big six
The top level domains (TLD other than .int.

bin
A directory that contains programs. Your home directory probably has a subdirectory named bin. The system has directories called /bin and /usr/bin.

Binary
The numbering systems used in computers memory and in digital communication. All characters are represented as a series of 1s and 0s. For example, the letter A might be represented as 01000001.

BIND
See Berkeley Internet Name Daemon (BIND)

Binding
A process that establishes the initial communication channel between the protocol driver and the network adapter card driver.

binding
A logical connection between a client process and a server process.

BIP
Bit Interleaved Parity: A method used at the PHY layer to monitor the error performance of the link. A check bit or word is sent in the link overhead covering the previous block or frame. Bit errors in the payload will be detected and may be reported as maintenance information.

BIS
Border Intermediate System.

B-ISDN
Broadband ISDN: A high-speed network standard (above 1.544 Mbps) that evolved Narrowband ISDN with existing and new services with voice, data and video in the same network.

BISUP
Broadband ISDN User's Part: A SS7 protocol which defines the signaling messages to control connections and services.

bit
A tiny piece of information that can be either a 1 or 0. Bits tend to get lumped onto groups of 8 bits called bytes.

BITNET
An academic and research network connecting approximately 2500 computers, often IBM mainframes. It provides interactive electronic mail, and file transfer services via a store-and-forward technique based on IBM NJE protocols. BITNET and Internet traffic are exchanged via several gateway hosts. It is now operated by CREN.

Bits
In binary data, each unit of data is a bit. Each bit is represented by either 0 or 1, and is stored in memory as an ON or OFF state.

B-LLI
Broadband Low Layer Information: This is a Q.2931 information element that identifies a layer 2 and a layer 3 protocol used by the application.

block
A unit of disk space containing one or more frags. See frag .

BMP
Bitmap format (for Windows )

BN
Bridge Number: A locally administered bridge ID used in Source Route Bridging to uniquely identify a route between two LANs.

BN
BECN Cell: A Resource Management (RM) cell type indicator. A Backwards Explicit Congestion Notification (BECN) RM-cell may be generated by the network or the destination. To do so, BN=1 is set, to indicate the cell is not source-generated, and DIR=1 to indicate the backward flow. Source generated RM-cells are initialized with BN=0.

BNF
Backus-Naur Form.

BOA
See Basic Object Adapter (BOA) .

BOCS
Berard Object and Class Specifier, an Object-oriented CASE tool from Berard Software Engineering.

Boehm B.
Proposed the COCOMO technique for evaluating the cost of a software project.

BOM
Beginning of Message: An indicator contained in the first cell of an ATM segmented packet.

BOOTP
See Boot Protocol (BOOTP)

Boot Protocol (BOOTP)
The protocol that defines how a diskless workstation obtains its network address from another host. NeXT workstations also use BOOTP when booted to determine their NetInfo information. Defined in RFC 951 and extended by RFC 2132. See also Dynamic Host Configuration Protocol (DHCP).

BoM
Bill of Materials.

BON
Better Object Notation. Used in the Esprit Business Classes project

Bookreader
DEC's CD-ROM-based online documentation browser.

Bookviewer
A hypertext documentation system from Oracle based on Oracle Toolkit. It allows the user to create private links and bookmarks, and to make multimedia annotations.

Boot Partition
The volume, formatted for either an NTFS, FAT, of HPFS file system, that contains the Windows NT operating system’s files. Windows NT automatically creates the correct configuration and checks this information whenever you start your system.

BOOM
Berard Object-Oriented Methodology - .

Border Node
A logical node that is in a specified peer group, and has at least one link that crosses the peer group boundary.

Border Gateway Protocol (BGP)
A protocol, defined in RFC 1163 ftp://ftp.isi.edu/in-notes/rfc1163.txt and later refined in RFC 1771 ftp://ftp.isi.edu/in-notes/rfc1771.txt, that allows the exchange of packets between networks, such as a company intranet and the Internet.

BOS
A data management system written at DESY and used in some HEP programs.

Bourne Shell
The Bourne shell is the most widely used Unix shell.It prompts you with $.Its program name is sh.

Bourne shell
A common UNIX shell

BPDU
Bridge Protocol Data Unit: A message type used by bridges to exchange management and control information.

BPM
Business Process Modelling.

BPP
Bridge Port Pair (Source Routing Descriptor): Frame header information identifying a bridge/LAN pair of a Source route segment.

BPR
Business Process Reengineering.

break Key
The Break Key is used before you log in when you are dialing on a modem to tell Unix that it has guessed wrong about which kind of modem you're using.You may have to press Break two or three times until you get a proper login: message. Some keyboards have a key labeled break. If yours does'nt and you're using a PC with a modem program, try Alt-B or check your modem program's help screen.

Bridge
A device that connects two segments of a network and data to one of the other based on a set of criteria.

bridge
Networking hardware that connects two network segments into one logical segment.

bridge
Networking hardware that connects two network segments into one logical segment.

Brightness
Light output measured at the face plate of the CRT; typically measured in foot lamberts (Fl). A minimum brightness level of 20Fl when viewing at full page size is considered acceptable.

Broadband
A service or system requiring transmission channels capable of supporting rates greater than the Integrated Services Digital Network (ISDN) primary rate.

Broadband Access
An ISDN access capable of supporting one or more broadband services.

Broadcast
Data transmission to all addresses or functions.

broadcast
One host broadcasts when it wants every machine (typically on a LAN) to receive the packet or information. See also anycast, multicast , unicast .

Browser
A tool for navigating around hypertext documents.

Browser
In order to be able to access the Web, you first need to be able to access the internet. You then need software which will let you look at all of the information available on the Web. This is often referred to as browsing and the software that lets you do this is called a browser. In the Math Department, the currently preferred browser on the UNIX machines and Macs is called Netscape, version 2.0.

Browser
A computer on a Microsoft network that maintains a list of computers and services available on the network

Browsing
The process of requesting the list of computers and services on a network from a browser.

BSD
Berkeley Source Distribution: the versions of UNIX developed and distributed by the University of California at Berkeley. Many commercial UNIX implementations such as SunOS and Dynix are derived from it.

BSD Unix
A version of Unix developed and distributed by the University Of California at Berkeley. BSD stands for Berkely Software Distribution.

BSI
British Standards Institution: a member of ISO.

BSP method
A CASE method from IBM .

BT
Burst Tolerance: BT applies to ATM connections supporting VBR services and is the limit parameter of the GCRA.

Btag
Beginning Tag: A one octet field of the CPCS_PDU used in conjunction with the Etag octet to form an association between the beginning of message and end of message.

B-TE
Broadband Terminal Equipment: An equipment category for B-ISDN which includes terminal adapters and terminals.

buffer
A small storage area in which information is stored temporarily until it is needed. Lots of things have buffers; printers frequently have buffers to store the next few lines or pages to print; emacs(a text editor)refers to its copies of the files you are editing as buffers.

Buffers
A reserved portion of memory in which data is temporarily held pending an opportunity to complete its transfer or from a storage device or another location in memory.

BUS
Broadcast and Unknown Server: This server handles data sent by an LE Client to the broadcast MAC address ('FFFFFFFFFFFF'), all multicast traffic, and initial unicast frames which are sent by a LAN Emulation Client.

BW
Bandwidth: A numerical measurement of throughput of a system or network.

Byte
A data unit of several bits smaller than a computer word: usually 8 bits.

byte
Eight bits in a row. That is a series of eight pieces of information, each of which can be either 1 or 0. A little higher math tells you that there are 256 different combinations of eight 1s and 0s.(256 is 2 to the 8th power.)There are therefore 256 different values for a byte of information. Most computers use a system of codes called ASCII to determine what each pattern means. The combination 01000001 means A, 01000010 means B, and 00001010 means "end of the line, start a new one."