ISDN PRI (Primary Rate Interface) typically consists of 23 B (Bearer) channels and 1 D (Data) channel, providing a total of 24 channels.
Here's the breakdown:
23 B channels: These are used for carrying voice, data, or video traffic. Each B channel has a bandwidth of 64 kbps.
1 D channel: This channel is used for signaling and control purposes. It operates at 64 kbps and is used for call setup, teardown, and other signaling functions.