Which statement about Basic Rate Interface (BRI) is true?

Which statement about Basic Rate Interface (BRI) is true?

• A. It provides four B channels at 128 kbps each and no D channel.
• B. It provides two B channels at 64 kbps each and one D channel at 16 kbps, and B channels can be aggregated to 128 kbps.
• C. It uses only voice data and no data signaling.
• D. It is a wireless ISDN standard.

Answer: (B)

ISDN Basic Rate Interface uses two 64 kbps B channels for user data and a 16 kbps D channel for signaling and control. When both B channels are used together, you get 128 kbps of user data, while the D channel handles setup and management. BRIs are wired, not wireless, and they are not described by four B channels or by “no signaling.” So the statement that correctly reflects BRI is that there are two B channels at 64 kbps each and one D channel at 16 kbps, with the B channels capable of aggregating to 128 kbps for data.

ISDN Basic Rate Interface uses two 64 kbps B channels for user data and a 16 kbps D channel for signaling and control. When both B channels are used together, you get 128 kbps of user data, while the D channel handles setup and management. BRIs are wired, not wireless, and they are not described by four B channels or by “no signaling.” So the statement that correctly reflects BRI is that there are two B channels at 64 kbps each and one D channel at 16 kbps, with the B channels capable of aggregating to 128 kbps for data.