If you are a B2BUA, couldnt we be able to send a RE-INVITE with out SDP towards the callee? The callee should provide all capabilities at that time.
Venkatesh On 4/14/06, Paul Kyzivat <[EMAIL PROTECTED]> wrote: > > Artem, > > [your call flow was mangled almost to the point of complete > incomprehensibilty by the time it reached my mail reader (Thunderbird). > I *think* I figured it out.] > > You need to say more about the players here. Is the SIP server an agent > for the callee? Is it a B2BUA? Or a "proxy"? > > If it is a "proxy" then you are out of luck. > > If it is a B2BUA, you have options, though they may start to get > complicated. It can answer the invite from the caller itself. Then it > can reinvite the callee, offering at least one of the codecs that had > been previously agreed and offering one that it does support as well, > listing the supported one first as preferred. If the one it supports is > accepted all is well. If not, it won't be able to do MOH, and may want > to reinvite again specifying a=inactive, or c=0. > > Paul > > Artem Naluzhny wrote: > > hi > > Here is the call scenario: > > Caller side SIP server Callee > side| | |@-> INVITE > ------------------>| || m=audio 16428 RTP/AVP > 4 0 2 8 100 101 || > | || @-> INVITE > ------------------>|| | m=audio 16428 RTP/AVP > 4 0 2 8 100 101| | > || |<- 200 OK > -------------------@| | m=audio 16460 RTP/AVP > 4 100 101| | ||<- > 200 OK -------------------@ || m=audio 16460 > RTP/AVP 4 100 101 || > | || > | |@-> re-INVITE --------------->| > || c=IN IP4 0.0.0.0 | | > > On-hold event has been detected and now the SIP server wants to playmy > own music-on-hold to callee side. But the problem is that SIPserver has no > the MOH in G723 codec but has it in G711 and G729 forexample. I know that > the callee side supports both G711 and G729codecs. The question is how to > ask callee side of established dialogfor full list of supported codecs? > > (Actually the same codec related issue exists for attended > transferhandling on SIP server side.) > > --tut > > _______________________________________________ > > Sip-implementors mailing list > > [email protected] > > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors > > > _______________________________________________ > Sip-implementors mailing list > [email protected] > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors > _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
