ISDN what are the features and operation?

Question

In detail what are the features operations and revelantant standards of ISDN.I have some information allready like

Integrated Services Digital Network is a set of digital transmission protocols defined by CCITT. The protocols are accepted by virtually all the world’s communications carriers as standard.
o It builds on groups of standard transmission channels. Bearer channels (or B channels) transmit user information at relatively high speeds, while separate Data channels (or D channels) carry call set-up, signaling and other information.


Two types of ISDN channels. B channels are clear channel "pipes" for user voice and data.
D channels are packet-switched links for call set-up and user data.


o It handles all types of information. Unlike some other digital communications technologies, ISDN handles all types of information - voice, data, studio-quality sound, still and moving images. They are all digitized, and transmitted at high speeds in the same flow of data.

Answer 1

some help here
http://alumnus.caltech.edu/~dank/isdn/isdn_ai.html#WHAT

Answer 2

The problem with ISDN is that it is limited to two 64K bearer channels. When bonded together, they permit 128K maximum, and there are now tricks to take a "nailed ISDN line" (one that's connected to the same place all the time, so there's no signalling or call setup required) and bond the "D" channel as well, for a maximum throughput of 144K.

ISDN has been replaced by other technologies now, most noticably ADSL, HDSL, SDSL, or some other flavor of DSL.

ISDN failed miserably because the phone companies priced it too high, and because technology leapfrogged right over it before it could become standardized.

In the telecom industry, we say that ISDN is an acronym for "I Still Don't Need-it."

Answer 3

Integrated Services Digital Network

Answer 4

no one uses ISDN anymore. it is slow compared to DSL.