| D channel
A wire used to perform call signaling and setup in establishing a
connection over ISDN. This packet-switched call data is carried on one
16-kbps line for Basic Rate Interface (BRI) service. Primary Rate
Interface (PRI) service uses a 64-kbps D channel. In some cases, the D
channel can also be used to carry user data. It is also sometimes referred
to as the delta channel. |