Types of ISDN

BRI offers 2 B-channels (64Kbps each) and one 16Kbps D-channel and rarely requires an upgrade of the actual cable involved, just an upgrade of the equipment at the exchange and at the subscriber's premises.

PRI is offered only over a T1 (North America) or E1 (Europe) line and offers either 23 or 30 B-channels (North America or Europe respectively) along with one 64Kbps D-channel.

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Introduction - Modems - ISDN - DSL - cable modems - Mobile comms - Conclusion - Glossary