Interworking Sip Update Messages; Interworking Sip Re-Invite To Update; Interworking Delayed Offer; Interworking Call Hold - AudioCodes Mediant 800B User Manual

28.9.8 Interworking SIP UPDATE Messages

The device supports interworking of the SIP UPDATED message. This enables
communication between UAs that generate UPDATE requests and those that do not
support the receipt of UPDATE requests. The device does not forward UPDATE requests
to IP Groups that do not support it. Instead, it sends a SIP response to the UPDATE
request which can either be a success or a failure, depending on whether the device can
bridge the media between the endpoints. The handling of UPDATE messages is configured
by the IP Profile parameter 'SBC Remote Update Support'.

28.9.9 Interworking SIP re-INVITE to UPDATE

The device enables communication between endpoints (IP Groups) that do not support re-
INVITE requests but support the UPDATE method, and vice versa. The device translates
the re-INVITE request to the UPDATE request, and vice versa. Note that if a re-INVITE
request arrives without SDP, the device generates the SDP and adds it to the outgoing
UPDATE request. To enable this feature, each IP Group needs to be configured with its
unique capabilities by associating it with a relevant IP Profile. For example, an IP Group
that supports UPDATE requests but not re-INVITEs would be configured as follows:

SBCRemoteUpdateSupport = 2 (Supported)

SBCRemoteReinviteSupport = 0 (Not Supported)
If a re-INVITE request needs to be forwarded to this IP Group, it is translated to an
UPDATE request.

28.9.10 Interworking Delayed Offer

The device supports interworking of INVITE messages with and without SDP between SIP
entities. The device enables sessions between endpoints (IP Groups) that send INVITEs
without SDP (i.e., delayed media) and those that do not support the receipt of INVITEs
without SDP. The device creates an SDP and adds it to INVITEs that arrive without SDP.
This intervention in the SDP offer-answer process may require transcoding. Delayed offer
is also supported when early media is present.
Employing IP Profiles, you can configure this interworking feature per SIP entity, using the
'SBC Remote Delayed Offer Support' parameter (see ''Configuring IP Profiles'' on page
396).
Note: For SIP entities that do not support delayed offer, you must assign extension
coders to its IP Profile (using the 'Extension Coders' parameter).

28.9.11 Interworking Call Hold

The device supports the interworking of call hold / retrieve requests between SIP entities
supporting different call hold capabilities:

Interworking SDP call hold formats. This is configured by the IP Profile parameter,
'SBC Remote Hold Format'.

Interworking the play of the held tone for IP entities that cannot play held tones locally.
This is configured by the IP Profile parameter, 'SBC Play Held Tone'.

Interworking generation of held tone where the device generates the tone to the held
party instead of the call hold initiator. This is configured by the IP Profile parameter,
'SBC Reliable Held Tone Source'.
User's Manual
Mediant 800B Gateway and E- SBC
628 Document #: LTRT-10296