- PC - Buzz - 1 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z *

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B2B = Business-to-business

> EDI

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Baan

 

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backbone

Betegnelsen for de datalinier, der forbinder de enkelte dele af Internettet med hinanden.

 

High speed data link connecting networks.

> ATM, FDDI

collapsed backbone - Multi-port Switch eller Router der fungerer som backbone

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BALUN = BALanced-UNbalanced

an impedance matching device enabling the use of nonstandard cables in a LAN

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bandwidth = båndbredde

1. Measure of the information capacity of a transmission channel.
2. The difference between the highest and lowest frequencies of a band that can be passed by a transmission medium without undue distortion, such as the AM band 535 to 1705 kilohertz.

 

2 methods: baseband, broadband

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Banyan Vines

 

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BAP/BACP = Bandwidth Allocation Protocol / Bandwidth Allocation Control Protocol

The protocol for managing dynamic bandwidth allocation with multilink PPP connections, and its control protocol.

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baseband

Transmission scheme in which the entire bandwidth, or data-carrying capacity, of a medium (such as a coaxial cable) is used to carry a single digital pulse, or signal, between multiple users. Because digital signals are not modulated, only one kind of data can be transmitted at a time.
Kun ét signal ad gangen, som optager hele båndbredden. Digital. - benyttes ved fx ethernet.
se bandwidth, broadband

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BASIC = Beginners All-purpose Symbolic Instruction Code

> Visual Basic

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baud = Bit at Unit Density

A measure of the speed of transmission of data; number of elements transmitted per second.
Overførselshastighed f.eks. for et modem. kbaud betyder kilobit pr. sek. og Mbaud betydet megabit pr. sek.

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BBC = Broadband Bearer Capability

A bearer class field that is part of the initial address message.

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BBS = Bulletin Board System

On-line tjeneste

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B-channel

se ISDN

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BCC = Blind Carbon Copy

E-mail adresse-felt hvor man kan skrive adresser på modtagere, som skal have en kopi af brevet.
NB: andre modtagere af brevet kan ikke se modtagerne i dette felt - og modtagere i dette felt kan ikke se modtagerne i de andre felter (det almindelige adresse-felt og CC-feltet).
>CC

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BCOB = Broadband Connection Oriented Bearer

-A - /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).
-X - /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.

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BDC = Backup Domain Controller

domæneserver i Windows NT
se PDC

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BDOS = Basic Disk Operating System

 

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BECN = Backward Explicit Congestion Notification

A bit in the frame relay header. The bit is set by a congested network node in any frame which is traveling in the reverse direction of the congestion. (In frame relay, a node can be congested in one direction of frame flow but not in the other.)

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Bell

103 = V.21
212A = V.22

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BER = Bit Error Rate

 

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BFT = Binary File Transfer

Fax af datafil.

 

BFT-NSF = BFT - Non Standard Facilities

by Microsoft

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BGA = Ball Grid Array

 

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BICI, B-ICI = Broadband Inter Carrier Interface

A carrier-to-carrier interface like PNNI but lacking some information offered by PNNI. Carriers are not likely to let their switches share routing information or detailed network maps with their competition's equipment. BICI now supports only permanent virtual circuits between carriers; the ATM Forum is currently addressing switched virtual circuits.

 

BICI SAAL = BICI 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 (AAL 5).

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BI-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.

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BIND = Berkeley Internet Name Domain

implementation of DNS server - used by many Internet hosts

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BinHex

Mac-standard til kodning af vedhæftede filer i e-mail - kan i PCer benyttes bl.a. af Netscape og Eudora.
> binær, hexadecimal, MIME

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binær (Eng: binary)

Afledt af 'bi' i betydningen 'to' (bicycle: to hjul, binocular: to øjne, bivogn: vogn nr 2).
I det 'binære talsystem' er grundtallet 2 og hvert ciffer (binary digit = bit) har 2 mulige værdier: 0 og 1
(I det 'decimale talsystem' er grundtallet 10 og hvert ciffer har 10 mulige værdier: 0, 1, ..., 9)
> hexadecimal

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BIOS = Basic In Out System

ROM-chip på bundkortet og videokortet - indeholder systemspecifik programkode, som kan håndtere adgangen til maskinens hardware.
BIOS på bundkortet indeholder også maskinens start-program - > Boot, POST
 
> APM (Advanced Power Management)
> AMI, Award, Phoenix

www.motherboards.org/bios.html

BIOS upgrade
> Intel CPU Overdrive

www.intel.com/overdrive/BIOS

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B-ISDN = Broadband ISDN

An ISDN technology suite designed for multimedia. The two transmission types are: ATM (Asynchronous Transfer Mode) and STM (Synchronous Transfer Mode).  

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B-ISSI = Broadband Inter Switching System Interface

- Between ATM nodes.

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bit = binary digit

Den mindste informations-enhed: ét ciffer i det binære talsystem med værdien 0 eller 1.
En gruppe på 8 bits kaldes en byte.
Datahastigheder angives ofte i bis per sekund (bps), kilobits pr sekund (Kbps) o.s.v.

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BITFTP

FTP via e-mail

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BITNET = Because It's There Network

- administration merged in 1989 with CSNET to form CREN. BITNET continued as international educational network.

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Bitstream

> TrueDoc

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Bluetooth

Et kommunikationssystem, udviklet af Ericsson. Bluetooth sender radiosignaler med meget lav effekt (ca. 0,08 mW), hvor rækkevidden er cirka ti meter. Bluetooth har p.t. en båndbredde på ca. 1 Mb/s, men der arbejdes på Bluetooth 2. generation, som tillader højere båndbredder og rækkevidder på op til 100 meter. Bluetooth benytter 2,4 GHz frekvensbåndet, som også benyttes af DECT-telefoner, WLAN, mikrobølgeovne m.fl., så der er meget støj, og dette går ud over Bluetooth's hastighed.

 

Teknikken kan benyttes til fx trådløs kommunikation med en bærbar computer, så brugeren kan overføre data fra fx Outlook uden brug af kabler.
>IrDA
 

Specification for a low-power, short-range RF network for interconnecting mobile devices such as laptops, cell phones and PC peripherals.

 

www.bluetooth.com

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BNC = Bayonet Neill-Concelman, British Naval Connector

Connector for coax cable, > 10BASE-2

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BOD = Bandwidth On Demand

Hastigheden på en enkelt ISDN B-kanal er 64 kbit, men ved brug af BOD (dvs. at en ekstra B-kanal tages i brug efter behov) bliver hastigheden fordoblet til 128 kbit.
- og det er over hvad en normal seriel port kan klare (max 115,2 kbps) - så skal man udnytte BOD må PC'en udvides med en højhastigheds-port.
> ISDN2

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bomb

or 'logical bomb' - dormant code, activation is triggered by a predetermined time or event.
> virus

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boot

= opstart.
'boot' er en forkortelse af 'bootstrap', som på engelsk betyder 'støvlestrop' - et lille håndtag øverst på støvlen som benyttes til at trække hele støvlen på plads.
Det lille startprogram, som benyttes til at trække hele operativsystemet på plads kaldtes derfor oprindeligt et 'bootstrap-program'.
I moderne computere ligger boot-programmet i en BIOS-chip på bundkortet - programmet tester maskinen (se POST) og indlæser operativsystemet (fx DOS eller Windows), som herefter overtager kontrollen med maskinen.
 
boot-disk

http://www.bootdisk.com/bootdisk.htm

en start-diskette, som indeholder et minimalt operativsystem (DOS), så maskinen kan startes selv om harddisken ikke indeholder et brugbart operativsystem.
Desuden indeholder disken hjælpeprogrammer, som kan bruges til klargøring af harddisken (FDISK og FORMAT) - og ofte også drivere til CD-ROM drevet, så et nyt operativsystem (fx Windows) kan installeres fra CD.

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Borland

> Paradox, Quattro Pro, Turbo Pascal

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bps = Bits Per Second

 

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bredbånd = broadband

Hurtig dataforbindelse.
>båndbredde

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BRI = Basic Rate ISDN, Basic Rate Interface

ISDN standards and specifications for provision of low-speed ISDN services. Supports two "B" channels of 64 Kbps each and one "D" channel of 16 Kbps on a single wire pair.
3 channels (2B+D) : two 64kbps B channels (data transmission) - one 16kbps D channel (control). The B channels may be combined for 128kbps

 

Basic Rate Interface (BRI) - The term ISDN or ISDN line is often used synonymously with the Basic Rate Interface. The Basic Rate Interface defines a digital communications line consisting of three independent channels: two B channels, each at 64 Kilobits per second, and one D channel at 16 Kilobits per second. For this reason the ISDN Basic Rate Interface is often referred to as 2B+D.

The B channels are used for carrying the digital information, whether computer data, digitized voice, or motion video with appropriate equipment. These B channels can be bonded or linked together to provide an aggregate 128 Kilobits per second data channel. The D channel is used to carry signaling and supervisory information to the network, and can also be used to carry packet-mode data over an X.25 network.

Each of the two B channels is treated independently by the network, allowing for simultaneous voice and data, or data only, connections to different locations. With specialized hardware and software, multiple B channel connections can be aggregated to achieve file transfer rates of several Megabytes of data per minute or more

> PRI

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bridge, bro

Arbejder på lag 2 (data link) - læser fysiske MAC-adresser.
En bro deler et lokalnet i flere logiske segmenter. Selektiv - filtrerer trafikken.
Benyttes også til konvertering mellem forskellige lokalnetsprotokoller - fx Ethernet og Token-Ring.

 

[IT-Lex]: Anvendes i datanet som betegnelse for en konverteringsenhed mellem to net. Der er tale om konvertering af såvel elektriske og signalmæssige formater (det fysiske lag) som protokollerne i dataoverførselslaget. En bro vil derfor have funktioner, som vedrører de to nederste lag i OSI-modellen. En bro kan virke som filter, dvs. kun overføre ikke-lokal trafik.
I lokalnet kan en bro også have funktioner fra OSI lag 3, dvs. rutning, og den kunne derfor benævnes router, men til forskel fra denne sker rutningen i broer ud fra MAC-adresser. Sådanne broer findes i varianterne "transparent bridge" og "source routing bridge".

 

[MS-CD]: 1. A device that connects networks using the same communications protocols so that information can be passed from one to the other. 
2. A device that connects two LANs (local area networks), whether or not they use the same protocols, and allows information to flow between them. The bridge operates at the ISO/OSI data-link layer.

 

> gateway, repeater, switch, router

routing bridge
Bro med router-egenskaber baseret på layer-2 MAC-adresser
> bridge/router, brouter

 

2 typer:

1. Spanning Tree Bridge, Learning Bridge, Transparent bro - kræver ingen programmering, lærer selv, opbygger adresse-tabel
2. Source Routing Bridge - i IBM netværk. Ruten frem til modtageren er lagret i datapakken - simple broer - hver computer vedligeholder sine egne ruter vha discovery packets 

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bridge/router

A device that can provide the functions of a bridge, router, or both concurrently. Bridge/router can route one or more protocols, such as TCP/IP and/or XNS, and bridge all other traffic.
se bridge: routing bridge, brouter

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bro

se bridge

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broadband = bredbånd

A data-transmission scheme in which multiple signals share the bandwidth of a medium. This allows the transmission of voice, data, and video signals over a single medium. Cable television uses broadband techniques to deliver dozens of channels over one cable.
Flere samtidige signaler ('kanaler'), som deler båndbredden. Analog modulering. Multiplex
> B-ISDN, bandwidth, baseband

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broadcast

"rundspredning" - fx i ethernet hvor alle pakker læses af alle computeres data-link-lag, men kun den med rette modtager-adresse accepterer pakken
> Firewall: Broadcast Storm
Broadcast Address - A special address that is reserved for simultaneous broadcast to all stations.
Broadcast Domain - Defines the set of all devices which will receive broadcast frames originating from any device within the set. Broadcast domains are normally bounded by routers.

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Broadway

A standard for running X-Windows over www.
En standard for dataudveksling mellem Windows- og UNIX-baserede netværk

The Open Group’s X Window System Release 6.3, code-named "Broadway" provides the ability to launch X clients from within a Web browser, either across a corporate intranet or the Internet.

By integrating X application access and Web protocols, X Web provides the ability to centrally deploy and manage X application access while eliminating the costs associated with training users on the semantics of the X Window System’s protocol. Further, access to enterprise applications from a Web-browser is accelerated, as X Web reduces the time to market by eliminating the need to re-code existing applications in Java.

X Web (Broadway) includes Low Bandwidth X (LBX), a transparent extension to the X server designed to improve the performance of X on WANs and slow dial-up connections.

www.broadwayinfo.com

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brouter

hybrid Bro/Router - fungerer som layer-3 router for routbare protokoller, som brouteren understøtter (TCP/IP), og som layer-2 bro for andre og ikke-routbare protokoller (NetBEUI).

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browser

Program, der bruges til at læse HTML-dokumenter. Dokumenterne (websider) hentes typisk på World Wide Web (Internettet). I browseren angives dokumentets adresse (evt via et link) på en web-server, som sender dokumentet. Browseren fortolker HTML-koden og viser resultatet på skærmen.
Fx Netscape Navigator og Microsoft Internet Explorer.
 

www.cnet.com/internet/0-3773.html : Browsers
www.download.com/2001-2137-0.html

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BSC = BrugerServiceCentret

> Sektornet

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BSD = Berkeley Software Distribution

Implementation of the UNIX operating system and its utilities developed and distributed by the University of California at Berkeley. BSD is usually preceded by the version number of the distribution, e.g., 4.3 BSD is version 4.3 of the Berkeley UNIX distribution. Many Internet hosts run BSD software, and it is the ancestor of many commercial UNIX implementations
> FreeBSD

http://www.auditmypc.com/acronym/BSD.asp

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BSI = British Standards Institution

Britisk standardorganisation.

www.bsi.org.uk

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BT = British Telecom

 

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btoa = binary to ascii

UNIX e-mail program til kodning af vedhæftede filer - dekodes med atob
> MIME

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buffer

A storage area used for handling data in transit. Buffers are often used to compensate for differences in processing speed between network devices.

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bus

Elektrisk forbindelse, som sammenkobler komponenterne i en computer. Bussens 'bredde' angiver, hvor mange bit der kan overføres samtidigt - fx består en 32-bit bus af 32 parallelle ledninger.
'Databussen' overfører data mellem fx RAM og CPU.
'Adressebussen' overfører adresser på data i RAM.

['bus' er afledt af latin 'omnibus' = 'for alle']

> AGP, AT-bus, FireWire, ISA, MCA, PCI, USB, VESA

 

bus network

[MS-CD]: A topology (configuration) for a LAN (local area network) in which all nodes are connected to a main communications line (bus). On a bus network, each node monitors activity on the line. Messages are detected by all nodes but are accepted only by the node(s) to which they are addressed. A malfunctioning node ceases to communicate but does not disrupt operation (as it might on a ring network, in which messages are passed from one node to the next). To avoid collisions that occur when two or more nodes try to use the line at the same time, bus networks commonly rely on collision detection or token passing to regulate traffic. Also called bus topology, linear bus.
> CSMA/CD, token bus network
> ring network, star network

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buzz

= 'buzzword' [Eng.]: et teknisk ord som kun forstås af de 'indviede'.
Benyttes ofte når hensigten ikke er at informere men at imponere. Med kendskab til ordenes betydning kan man dog nøjes med at lade sig informere.
> acronym

www.buzzwhack.com : Buzz Words
www.investopedia.com/categories/buzzwords.asp

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byte

Lager-enhed som benyttes i computere - i hukommelsen (RAM) og på disks. Alla data opbevares i bytes (se KB, MB, GB). Hver byte er sammensat af 8 bits.

Da en bit kan have 2 værdier (0 og 1), kan en byte have 2*2*2*2*2*2*2*2 = 2⁸ = 256 værdier (fra 0 til 255). Dataværdierne kan repræsentere programinstruktioner eller dokument-data - fx bliver hvert tegn i denne tekst gemt i en byte.

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båndbredde

Et mål for en dataforbindelses hastigheden fx målt i Kilobit pr sekund (Kbps).
Dataflow per tidsenhed = rate, speed, bps, MHz

> bandwidth, bredbånd