Basic Rate Interface definition communications
(BRI, 2B+D, 2B1D) An Integrated Services Digital Network
channel consisting of two 64 kbps
"bearer" (B) channels and one 16 kbps "delta" (D) channel, giving a total data rate of 144 kbps. The B channels are used for voice or user data, and the D channel is used for control and signalling and/or X.25 packet
networking. BRI is the kind of ISDN interface most likely to be found in residential service.