isdn uses b & d channels for data.
isdn uses b & d channels for data.
isdn uses b & d channels. what is d channel use for?
data
each b-channel carries data, voice, and other services. the d-channel carries control and signaling information. larger connections are possible using pri pairing. a dual t1-pri could have 24 + 23 = 47 b-channels and 1 d-channel (often called "47b + d"), but more commonly has 46 b-channels and 2 d-channels thus providing a backup signaling channel. the concept applies to e1s as well and both can include more than 2 pris. when configuring multiple t1's as isdn-pri's, it's possible to use nfas (non-facility associated signalling) to enable one or two d-channels to support additional b-channels on separate t1 circuits.









































section::::application.
primary rate interface
channel use









































channel use is a quantity used in signal processing or telecommunication related to symbol rate and channel capacity. capacity is measured in bits per input symbol into the channel (bits per channel use). if a symbol enters the channel every "t" seconds (for every symbol period a symbol is transmitted) the channel capacity in bits per second is "c/t". the phrase "1 bit per channel use" denotes the transmission of 1 symbol (of duration "t") containing 1 data bit.









































section::::see also.









































bullet::::- adaptive communications









































bullet::::- end instrument









































bullet::::- spectral efficiency and modulation efficiency in (bit/s)/hz
channel use