Three points of interest here. 1) By default, NUA supports the 100rel extension described in RFC3262. Since the proxy is sending a 183 response, it seems likely that it is requesting a PRACK. Have those messages been omitted in the provided call flow?
2) If the proxy was not requesting a PRACK, Sofia-SIP is required to ignore the SDP in the 200 OK, in accordance with rules in RFC 3261, Section 13.2.1. 3) If arguing with the vendor isn't an option, you should be able to pull the unparsed SDP from the sip_t structure. From there, a session re-negotiation might sync up the stack. Hope this helps. -Jarod From: Louis Guindon [mailto:louisguin...@vtech.ca] Sent: Wednesday, October 12, 2011 1:37 PM To: sofia-sip-devel@lists.sourceforge.net Subject: [Sofia-sip-devel] 183 early media description different from 200Ok media desription Dear All, I am experiencing a problem with the Sofia SIP stack with early media. Here the flow: A (Sofia) Proxy B |-----------INVITE----------->| | | |----- INVITE ---------->| | | | | |<------ 100 ------------| |<-----------100--------------| | | | | |<-----------183--------------| | | (Media Source Proxy) | | |<===========RTP=============>| | | |<------ 200 ------------| |<-----------200--------------| | | (Media Source B) | | |<===========================RTP=======================| | | | |------------ACK------------->| | | |------- ACK ----------->| | | | During the call setup, the Proxy sends early media so tones (ringback) is generated by the proxy. When the endpoint B answers the call, the SDP in the 200OK contains media description for the endpoint B. The RTP Problem: The stack seems to assume that the SDP payload received from a 183 would be the same as the one received with the 200OK. Thereof, the stack ignore reporting the SDP from the 200OK and doesn't intialize the SDP structure pointer when the stack has previsously received SDP as part of the 183. The application cannot retrieve the SDP information to update the RTP stream direction which cause one-way audio. Question: How can we force the stack to populate the NUA SDP structure members in that case? Any idea would be welcomed... Regards, Louis Guindon ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2d-oct _______________________________________________ Sofia-sip-devel mailing list Sofia-sip-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sofia-sip-devel
