Christer, Christer Holmberg <christer.holmberg@xxxxxxxxxxxx> Tue, 20 Apr 2010 12:27:33 +0200 >Hi, > >>Before sending an answer, >>- An UAS MAY send unreliable provisional responses with a SDP. >>- And the SDP MUST be identical to an answer SDP. >> >>After sending an answer, >>- The UAS should not insert a SDP in any response. >> >>Is this OK? > >That text still doesn't say what an SDP inserted after sending >the answer means, only that it should not be sent. The SDP means nothing. it is neither an offer nor an answer. >I still don't see why we need to make a separation about SDP >sent before and after the answer, because in both cases the >SDP must be identical to the answer. 1. RFC3261 says that UAS MAY send it before the answer and doesn't say nothing after the answer. 2. The SDP MUST be ignored by UAC. it is meaningless. 3. if another o/a exchange is occured (using UPDATE or PRACK), it is not even a confirmation. >And, again, I know there are many implementations that send >a copy of the SDP after the SDP answer has been sent, so >instead of saying that it should not be done I think it is >much more important to say that, if it is done, it must be >identical to the SDP answer. In other words, to make it clear >that the UAS can not send a NEW offer (or updated answer) >in a subsequent response after the SDP answer has been sent. Since UAC MUST ignored it, there is no problem on a interworking. Why must it be identical to the SDP answer? Regards, Shinji >Regards, > >Christer > >Hans Erik van Elburg <ietf.hanserik@xxxxxxxxx> >Mon, 19 Apr 2010 13:55:41 +0200 >>> - An UAS MAY insert a SDP body that is identical to the SDP >>> answer, in an unreliable provisional response before the SDP >>> answer has been sent. >>> >>> - The UAS MUST NOT insert a SDP body that is not identical to >>> the SDP answer, in an unreliable provisional response before >>> the SDP answer has been sent. >>> >>This is terribly confusing. Very probabe that noone will get it right. >>Triple negation. And talking about sending and answer before the >>answer has been sent. ??? >> >> >>> - The UAS MUST NOT insert a SDP body in any response after the >>> SDP answer has been sent. >>> >>This means that you can't send it again after you've send it in an >>unreliable provisional response. Do you want tto say that? >> >>/Hans Erik van Elburg _______________________________________________ Sipping mailing list https://www.ietf.org/mailman/listinfo/sipping This list is for NEW development of the application of SIP Use sip-implementors@xxxxxxxxxxxxxxx for questions on current sip Use sip@xxxxxxxx for new developments of core SIP
