release (ISDN) (REL)

The Release Message (REL) is a signaling message that can be sent in sections in both directions of an ISDN network. This command initiates the disconnection of the user channel. For example, one exchange may inform another in the REL message that it is in congestion; whereupon the other reduces the traffic load.

The release message is described in ITU-T Recommendations Q.762, Q.763 and Q.764.