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Overview
Integrated Services Digital Network (ISDN) is an internationally
Two types of ISDN services are currently available:
•Basic Rate Interface (BRI)
•Primary Rate Interface (PRI)
Both BRI and PRI ISDN services have two types of digital channels: one ISDN D channel and multiple ISDN B channels.
•The ISDN D channel is generally used to transmit signalling and control information such as
•The ISDN B channels transfer data (voice, circuit- switched data, and
5536 PRI RAS Communications Controller Users Guide | 189 |