I was surprised to find > * There were implementations that offered an m-line with codecs A, B, > and C, got an answer with C, then got upset when they got RTP with A > (which is quite legal).
On the list (like others who argued about it I think). I had some offline discussions with some of the members on this. While I agree this seems legal, this seems very counter-intuitive and may result in wasted resources, would it not? For example, if the offerer is a conference bridge or a transcoder, and has a limited number of codecs of each type he offers, why should it hold on to one codec of each type for the duration of the session, even though the answerer has not supported it? Any particular reason why this should be continued as a legal scenario? Would it not be possible change it to say that the Offerer needs to expect only those codecs which answerer has explicitly supported in the answer? Regards, Ravi. -- Ravishankar. G. Shiroor Wipro Technologies, Bangalore. [EMAIL PROTECTED] -- > -----Original Message----- > From: Robert Sparks [mailto:[EMAIL PROTECTED] > Sent: Tuesday, November 20, 2007 2:38 AM > To: sip List > Subject: [Sip] SIPit 21 : Topics that attendees argued about > > Digging through my notes: > > Here are some of the topics where people were arguing. I'm capturing > the smaller topics here. Larger arguments will get their own message. > > * There were arguments about the dynamic payload map from numbers to > codecs (identified in the SDP and sent in the RTP) being the same in > the offer and the answer . The spec says they SHOULD. Some > implementations were insisting they MUST. > * There were arguments around preserving the relative order of codecs > on an m-line between the offer and the answer. The specs say SHOULD. > * There were implementations that offered an m-line with codecs A, B, > and C, got an answer with C, then got upset when they got RTP with A > (which is quite legal). > * There were arguments about deleting rejected m-lines on re-invites > (which you cannot do), and on reusing the slot they occupy in re- > invites (which you can do). > * There were implementations that didn't add the refresher tag in a > session-refresh message when they were the refresher and there were > arguments about whether that meant the other side could take the role. > * Several implementations handled a=sendonly as a session attribute, > but not a media attribute - it can appear in either place. > > > > _______________________________________________ > 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
