Avaya Communication Manager Administrator's Manual page 1547

Disconnect Supervision-In
This field indicates whether Avaya Communication Manager receives disconnect supervision
for incoming calls over this trunk group. It appears when the Direction field is incoming or
two-way. (If the Direction field is outgoing, Communication Manager internally sets this field
to n.)
The entry in this field is crucial if you allow trunk-to-trunk transfers. (To allow trunk-to-trunk
transfers involving trunks in this group, this field must be y and the Trunk-to-Trunk Transfer
field on the Feature-Related System Parameters screen must be y).
If a user connects 2 trunks through conference or transfer, and neither far-end media server or
switch on the resulting connection provides disconnect supervision, the trunks involved will not
be released because Avaya Communication Manager cannot detect the end of the call.
Communication Manager will not allow trunk-to-trunk transfers unless it believes that at least
one party on the call can provide disconnect supervision. Therefore, setting this field incorrectly
may cause trunks to become unusable until the problem is detected and the trunks are reset.
Valid entries
y
n
!
CAUTION:
In general, U.S. central offices provide disconnect supervision for incoming calls
CAUTION:
but not for outgoing calls. Public networks in most other countries do not provide
disconnect supervision for incoming or outgoing calls. Check with your network
services provider.
Usage
Enter y to allow trunk-to-trunk transfers involving trunks in
this group.
Enter y if the far-end server/switch sends a release signal
when the calling party releases an incoming call, and you
want to make the far-end server/switch responsible for
releasing the trunk.
Enter y to enhance Network Call Redirection.
Enter n if the far-end server/switch doesn't provide a
release signal, if your hardware can't recognize a release
signal, or if you prefer to use timers for disconnect
supervision on incoming calls. Entering n prevents
trunk-to-trunk transfers involving trunks in this group.
Trunk Group
Issue 1 June 2005 1547