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Glossary

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bus topology

A linear LAN architecture in which transmissions from var-

ious stations on the network are reproduced over the length of the medium
and are accepted by all other stations. Compare with: ring and star.

bus

Any physical path, typically wires or copper, through which a digital

signal can be used to send data from one part of a computer to another.

BUS

broadcast and unknown servers: In LAN emulation, the hardware or

software responsible for resolving all broadcasts and packets with unknown
(unregistered) addresses into the point-to-point virtual circuits required by
ATM. See also: LANE, LEC, LECS, and LES.

BX.25

AT&T's use of X.25. See also: X.25.

bypass mode

An FDDI and Token Ring network operation that deletes

an interface.

bypass relay

A device that enables a particular interface in the Token

Ring to be closed down and effectively taken off the ring.

byte

Eight bits of binary.

byte-oriented protocol

Any type of data-link communication protocol

that, in order to mark the boundaries of frames, uses a specific character
from the user character set. These protocols have generally been superseded
by bit-oriented protocols. Compare with: bit-oriented protocol.

cable modem

A cable modem is not actually an analog device, like an

asynchronous modem, but rather a customer access device for linking to a
broadband cable network. These devices are typically bridges that have a
COAX connection to link to the cable network and a 10BaseT Ethernet con-
nection to link to the user's PC.

cable range

In an extended AppleTalk network, the range of numbers

allotted for use by existing nodes on the network. The value of the cable
range can be anywhere from a single to a sequence of several touching net-
work numbers. Node addresses are determined by their cable range value.

CAC

Connection Admission Control: The sequence of actions executed by

every ATM switch while connection setup is performed in order to deter-
mine if a request for connection is violating the guarantees of QoS for estab-
lished connections. Also, CAC is used to route a connection request through
an ATM network.

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