AudioCodes Mediant 1000B User Manual page 968

Parameter
User's Manual
send an alarm on the trunk.
When connectivity is restored for the Busy Out feature or the Trunk
Group is unlocked, the device clears the alarm.
Note: For partially configured trunks (only some channels
configured), this option only rejects new calls for the trunk; no alarm
is sent.

[4] Block = (Applicable only to CAS) Blocks the B-channels.

Graceful out-of-service disabled: The device rejects new
incoming calls and immediately blocks all channels (idle and
busy).

Graceful out-of-service enabled: The device rejects new
incoming calls and blocks all channels (idle and busy) only when
the graceful period expires.
When connectivity is restored for the Busy Out feature or the Trunk
Group is unlocked, the device unblocks all the B-channels.

[5] Service and D-Channel = (Applicable only to T1 ISDN variants
that support this method) Sends ISDN Service messages to indicate
out-of-service or in-service state and takes the D-channel down or
brings it up.

Graceful out-of-service disabled:
- Fully configured trunk (all channels): The device rejects new
incoming calls and only takes the D-channel down.
- Partially configured trunk (only some channels configured):
The device rejects new incoming calls and sends out-of-service
Service messages to all the configured channels (D-channel
remains up).

Graceful out-of-service enabled: The device rejects new
incoming calls and does the following:
- Fully configured trunk (all channels):
> If all channels are idle when the graceful period begins, the
device immediately takes the channels out-of-service without
sending out-of-service Service messages and instead, only
takes the D-channel down.
> If at least one channel is busy during the graceful period, the
device immediately takes all idle channels out-of-service and
sends out-of-service Service messages to these B-channels.
Thus, the PSTN/PBX side can detect that these calls are in out-
of-service state and does not send new calls to these out-of-
service channels, eliminating the scenario of loss of calls due to
rejection.
> If a channel is released (call ends) during the graceful period
and there are still other busy channels, the device sends an out-
of-service Service message to the idle channel.
> When the last channel is released in the trunk (or Trunk
Group), the device takes all the channels out-of-service (locks
the Trunk Group) without sending an out-of-service Service
message; instead, it only takes the D-channel down.
When connectivity is restored for the Busy Out feature or the
Trunk Group is unlocked, the device brings the D-channel up
again without sending any Service messages to the B-channels.
- Partially configured trunk (only some channels configured):
The device places all channels out-of-service only after the
graceful period expires, by sending out-of-service Service
messages to the B-channels (the D-channel remains up).
968
Mediant 1000B Gateway and E- SBC
Description
Document #: LTRT-27044