> Hello! > > Consider an inbound call starting at an ITSP that is trying > to establish a call with extension 202. > Consider another phone (lets say extension 206) that attempts > to do a call pickup while phone 202 is Ringing. > 206 sends sipxbridge an INVITE with SDP OFFER and a Replaces header. > [ Note at this point that the ITSP is currently trying to > establish a call with 202 so the SDP answer has not gone back > from 202. ] > > sipxbridge, sends back an SDP offer to 206 in the OK using > the SDP offer from the ITSP.
As far as 206 is concerned, the SDP carried in the 200 OK it receives *is* the SDP answer which completes the Offer/Answer cycle and explains why the Ack from 206 does not carry an SDP body. The obvious problem here is that the SDP offer generated by the ITSP is being provided as an SDP answer to 206's SDP offer when the two SDPs do not, in reality, have that offer/answer relationship which will lead to media negotiation problems in many cases. Thinking out loud here but if the ITSP does not support INVITE with replaces then perhaps your best bet is to craft an SDP answer based on your knowledge of the offers from the ITSP and 206 and provide it to both 206 and the ITSP in the 200 Oks you send them. > > I would expect at this point that 206 would answer with an > SDP ANSWER in the ACK but it responds to sipxbridge with ACK > with no SDP. > > > Is this a bug in the phone or is my understanding flawed? > Traces can be posted if needed. > > > > Thanks in advance > > Ranga > > > -- > M. Ranganathan > _______________________________________________ > sipx-dev mailing list > [email protected] > List Archive: http://list.sipfoundry.org/archive/sipx-dev > Unsubscribe: http://list.sipfoundry.org/mailman/listinfo/sipx-dev > _______________________________________________ sipx-dev mailing list [email protected] List Archive: http://list.sipfoundry.org/archive/sipx-dev Unsubscribe: http://list.sipfoundry.org/mailman/listinfo/sipx-dev
