ADTRAN ISU 2X64 user manual Glossary, Asynchronous transmission

Glossary

asynchronous transmission

Not Synchronous. A method of data transmission which allows characters to be sent at irregular intervals by preceding each character with a start bit and following it with a stop bit. The timing of the transmission is not determined by the timing of a previous character. Applications include communication between most small computers (especially PCs) and mainframes, lower speed transmission, and less expensive computer transmission systems. See Synchronous.

B-channel

64 kbps bearer channel used for voice, circuit, or packet switched data.

bandwidth

The range of electrical frequencies a device is capable of handling. The amount of bandwidth a channel is capable of carrying tells you what kinds of communica- tions can be carried on it. For example, a wide band circuit can carry a TV channel. A wide band circuit that is capable of providing one video channel can also pro- vide 1,200 voice telephone channels.

bearer service

As defined by CCITT standards, a type of telecommunication service that provides the capability for the transmission of information between user-to-network inter- faces. Bearer services defined for ISDN are circuit mode and packet mode.

BONDING mode 1 protocol

Industry standard B-channel aggregation protocol. Developed by the Bandwidth on Demand Interoperability Group.

BRA

basic rate access. The BRA includes two 64 kbps B-channels and one 16 kbps D- channel. Also known as Basic Rate Interface (BRI).

bridging

The technique whereby additional stations may be served from a two-point facility by extending the facility from a bridge at one of the facility’s terminating points.

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