It is not clear from the call flow if the 200 OK is for PRACK or INVITE? I guess you meant 200 OK for Invite. If that is the case, I think the RFC is clear that the answer sdp is optional in it and if it does have an answer sdp, it MUST be idential to answer in 18x. But I think the offer-answer draft has clarified it further that it should not have any answer sdp. This is probably harsh in case of one offer-answer exchange, but makes sense if there are multiple early dialog offer-answer exchanges in say Prack/200 OK or using UPDATE.
Sanjay >-----Original Message----- >From: Robert Sparks [mailto:[EMAIL PROTECTED] >Sent: Monday, November 19, 2007 4:14 PM >To: sip List >Subject: [Sip] SIPit21: SDP in a 200OK when using 100rel > >There was a lot of discussion and disagreement at SIPit21 >about whether the following 200 OK is allowed (or should) have >SDP in it: > >INVITE (offer) >--------> >18x (with 100rel) (answer) ><-------- >PRACK >---------> >200 OK (can this carry SDP?) ><--------- >ACK >---------> > >I couldn't find anything definitive in RFC form. Paul's >offeranswer draft talks about this I think. > >If I understand things, the right answer here is that it's not >supposed to carry any SDP and that you should ignore it if it shows up. > >The question is, other than waste, what can go wrong if it is there? >When we end up with clear text around the requirement, will it >say SDP SHOULD NOT, or MUST NOT appear? > >Or do I have this wrong? > >RjS > > >_______________________________________________ >Sip mailing list https://www1.ietf.org/mailman/listinfo/sip >This list is for NEW development of the core SIP Protocol Use >[EMAIL PROTECTED] for questions on current sip >Use [EMAIL PROTECTED] for new developments on the application of sip > _______________________________________________ Sip mailing list https://www1.ietf.org/mailman/listinfo/sip This list is for NEW development of the core SIP Protocol Use [EMAIL PROTECTED] for questions on current sip Use [EMAIL PROTECTED] for new developments on the application of sip
