[OpenSIPS-Users] mediaproxy and reinvites

[Dan Pascu]

On Thursday 23 April 2009, Uwe Kastens wrote:
> Hello list,
>
> sorry for the not very specific question, but I am trying to find out,
> how to handle REINVITE with mediaproxy correctly.
>
> If I have a call with T38 its common that UAs will start with a codec
> ALAW/ULAW and changes later on to T38. My problem is, that this
> reinvite is not correctly handled by mediaproxy, since the rtp IP is
> not modified.
>
> If I will receive an INVITE without totag I will use
> engage_media_proxy();. What is the correct way to handle the new rtp
> session. End the current media_proxy_session and start a new one, or
> should I engage another media_proxy_session?

If you use engage_media_proxy(), you need to do nothing. Every re-INVITE 
and other in dialog messages are processed automatically. A re-INVITE 
used to start T38 is part of the original dialog, so you cannot call 
engage_media_proxy() again even if you want to, because no new dialog is 
started to trigger a new media session.

If the SDP is not modified, it may be a bug. We have tested T38 fax 
support and it worked for us. You need to figure out from the opensips 
and mediaproxy logs what is happening (i.e. is mediaproxy contacted by 
opensips or is that the mediaproxy module is not even seeing the 
re-INVITE?).

-- 
Dan