Avaya Communication Manager Administrator's Manual page 1548

Screen Reference
Disconnect Supervision-Out
This field indicates whether Communication Manager receives disconnect supervision for
outgoing calls over this trunk group. It appears when the Direction field is either outgoing or
two-way. (If the Direction field is incoming, 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 server/switch on the resulting
connection provides disconnect supervision, the trunks involved won't be released because
Communication Manager can't 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.
Also, remember that Avaya Communication Manager must receive answer supervision on
outgoing analog CO, FX, WATS, Tie, Tandem, and Access trunks before it will recognize a
disconnect signal. If this trunk group does not receive answer supervision from the far-end
server/switch, and you enter y in this field, Avaya Communication Manager will internally set the
field to n.
Valid entries
y
n
!
CAUTION:
Do not set this field to y unless you are certain that the far-end server/switch will
CAUTION:
provide answer supervision and disconnect supervision. Most public networks do
not provide disconnect supervision over analog trunks. Check with your network
services provider.
1548 Administrator Guide for Avaya Communication Manager
Usage
Enter y to allow trunk-to-trunk transfers involving trunks
in this group.
Enter y if the far-end sends a release signal when the
called party releases a call an outgoing call, and you
want to make the far-end responsible for releasing the
trunk.
The Answer Supervision Timeout field must be 0 and
the Receive Answer Supervision field must be y for
the switch to recognize a y entry.
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 outgoing calls. Entering n
prevents trunk-to-trunk transfers involving trunks in this
group.