[OpenSIPS-Users] 302 handling in openser

[sai at 800pbx.com]

We have a setup where we are using Microsoft Speech Server (MSS) to
connect to Asterisk through Openser. This was done as MSS uses TCP only
and Asterisk only UDP. The connection is something like shown below:

MSS <---->Openser<--->Asterisk<--->SIP Phones

Now, when a SIP Invite is sent to MSS from SIP UA through openser, Speech
server sends back a 302 message containing a maddr field populated with
the new IP Address where the UA must contact. This is forwarded back to
the SIP UA which doesnt know how to handle this. Moreover, the transport
is TCP instead of UDP which creates more problems.

We would like Openser to handle the 302 message and re-direct the Invite
message to the new IP address got from the maddr field. How can we
populate this through Openser?

In earlier posts, it was mentioned that uac_redirect module can be used to
handle the 302 but how exactly can the maddr field read and Invite
populated with the new IP address is not clear.

In one of the SIP users posts, the maddr usage was mentioned as :

"In some rfc 2543 implementations it had
been used to force an alternative route to the the one specified in R-URI,
however , this is discouraged by the 3261 spec and the loose-routing
mechanism is provided instead."

However, the maddr is still being utilised by systems to populate the
alternate routes.

Any help regarding how can we handle the 302 will be useful for us. Using
Transformations module in onreply_route block did not help our cause.
Also, we have tried using replace_body and replace_body_all with
hard-coded values for the ip addresses did not do the trick.

Please help us in this regard.

Regards,
Sai.