Glossary of terms - BRI - Basic Rate Interface

An ISDN BRI interface allows a speed of up to 128 Kbit/s, and consists of two B-channels, each having a speed of 64 Kbit/s, and a D-channel, with a speed of 16 Kbit/s.The B-channels transmit user data and voice. The D-channel is a service channel designed for transmission operators.