AudioCodes Mediant 600 User Manual page 672

Parameter
Web/EMS: TGRP Routing
Precedence
User's Manual
possible). The Contact header in the outgoing SIP INVITE (Tel-to-IP
call) contains "tgrp=<source trunk group ID>;trunk-context=<gateway
IP address>". The <source trunk group ID> is the Trunk Group ID
where incoming calls from Tel is received. For IP-Tel calls, the SIP
200 OK device's response contains "tgrp=<destination trunk group
ID>;trunk-context=<gateway IP address>". The <destination trunk
group ID> is the Trunk Group ID used for outgoing Tel calls. The
<gateway IP address> in "trunk-context" can be configured using the
SIPGatewayName parameter.

[3] Hotline = Interworks the hotline "Off Hook Indicator" parameter
between SIP and ISDN:

For IP-to-ISDN calls:
- The device interworks the SIP tgrp=hotline parameter
(received in INVITE) to ISDN Setup with the Off Hook Indicator
IE of "Voice", and "Speech" Bearer Capability IE. Note that the
Off Hook Indicator IE is described in UCR 2008 specifications.
- The device interworks the SIP tgrp=hotline-ccdata parameter
(received in INVITE) to ISDN Setup with an Off Hook Indicator
IE of "Data", and with "Unrestricted 64k" Bearer Capability IE.
The following is an example of the INVITE with tgrp=hotline-
ccdata:
INVITE sip:1234567;tgrp=hotline-ccdata;trunk-
context=dsn.mil@example.com

For ISDN-to-IP calls:
- The device interworks ISDN Setup with an Off Hook Indicator
of "Voice" to SIP INVITE with "tgrp=hotline;trunk-
context=dsn.mil" in the Contact header.
- The device interworks ISDN Setup with an Off Hook indicator
of "Data" to SIP INVITE with "tgrp=hotline-ccdata;trunk-
context=dsn.mil" in the Contact header.
- If ISDN Setup does not contain an Off Hook Indicator IE and
the Bearer Capability IE contains "Unrestricted 64k", the
outgoing INVITE includes "tgrp=ccdata;trunk-context=dsn.mil". If
the Bearer Capability IE contains "Speech", the INVITE in this
case does not contain tgrp and trunk-context parameters.

[4] Hotline Extended = Interworks the ISDN Setup message's hotline
"OffHook Indicator" Information Element (IE) to SIP INVITE's
Request-URI and Contact headers. (Note: For IP-to-ISDN calls, the
device handles the call as described in option [3].)

The device interworks ISDN Setup with an Off Hook Indicator of
"Voice" to SIP INVITE Request-URI and Contact header with
"tgrp=hotline;trunk-context=dsn.mil".

The device interworks ISDN Setup with an Off Hook indicator of
"Data" to SIP INVITE Request-URI and Contact header with
"tgrp=hotline-ccdata;trunk-context=dsn.mil".

If ISDN Setup does not contain an Off Hook Indicator IE and the
Bearer Capability IE contains "Unrestricted 64k", the outgoing
INVITE Request-URI and Contact header includes
"tgrp=ccdata;trunk-context=dsn.mil". If the Bearer Capability IE
contains "Speech", the INVITE in this case does not contain tgrp
and trunk-context parameters.
Note: IP-to-Tel configuration (using the PSTNPrefix parameter)
overrides the 'tgrp' parameter in incoming INVITE messages.
Determines the precedence method for routing IP-to-Tel calls -
according to the Inbound IP Routing Table or according to the SIP 'tgrp'
672
Mediant 600 & Mediant 1000
Description
Document #: LTRT-83313