Hi Ankur, Thanks for your clarification. My question still remains. In the offer from A does not have the support for payload no 101. So why you are saying it A SHOULD use it towards B instead of BYE. where only B has mentioned any payload support on 101. What is the basis of A should do that activity ? Is it best possible SDP negotiation in case not exact matching ?
Moreover how will B sends the telephony event with payload 99. B has not mentioned it support for payload 99. Thanks Sourav On Tuesday, 4 November 2014 9:48 PM, ankur bansal <abh.an...@gmail.com> wrote: Hi Saurav I believe there is no issue due to rtpmap as its required only for dynamic payloads and not for static payloads . Reason of UE A sending BYE could be mismatch in payload no for telephony event . A is sending 99 but B is sending 101 .So A finds this wrong and send BYE But UE Ashould not send BYE and accept this answer sending telephony events with payload no 101 instead of 99 which is expected by UE B. And UE B needs to send telephony events with payload no 99 towards UE A. Hope this helps Thanks & Regards Ankur Bansal On Tue, Nov 4, 2014 at 9:12 PM, Sourav Dhar Chaudhuri <sourav_mi...@yahoo.co.in> wrote: Hi, > I am observing a behavior SDP negotiation. In the Below Example just After > Media Negotiation. A is sending BYE without any media flow . Please refer the > below call flow & my query. > > >A --------------------------- INVITE with SDP -------------------------> B > >########## SDP details in Offer ############## > >v=0 >o=- 1414764441 1414764441 IN IP4 172.29.62.182 >s=Basic Session >c=IN IP4 172.29.62.182 >t=0 0 >m=audio 37620 RTP/AVP 18 8 0 99 106 107 >a=rtpmap:99 telephone-event/8000 >a=fmtp:99 0-15 >a=rtpmap:106 PCMU/8000 >a=rtpmap:107 PCMA/8000 >a=ptime:20 > >A <------------------------- 100 Trying -------------------------------------- > B > >A <------------------------ 180 Ringing >(unreliable)------------------------------------- B > >A <------------------------ 200 OK with SDP ------------------------------ B > >########## SDP details in Answer ################ > >v=0 >o=0000000000 37448557 1 IN IP4 172.29.62.11 >s=- >c=IN IP4 172.29.62.11 >t=0 0 >m=audio 53378 RTP/AVP 8 101 >a=sendrecv >a=ptime:20 >a=rtpmap:101 telephone-event/8000 >a=fmtp:101 0-15 > >A -------------------------- ACK -------------------------------------------> >B >A -------------------------- BYE ------------------------------------------> >B > >the call is getting disconnected without any media transfer. > >I can see there are six codecs [ 18 8 0 99 106 107 ] with attribute for only >for three [ 99 106 107 ] in SDP offer. Those three [ 99 106 107 ] only >having rtpmap details. > >But in SDP answer two codec [ 8 101 ] with attribute for only [ 101 ]. The >rtpmap is also for only [ 101 ]. > >So is the A is behaving correctly ? Whether there is failure in SDP >negotiation? If yes then why? > > > > >Regards, >Sourav Dhar Chaudhuri >_______________________________________________ >Sip-implementors mailing list >Sip-implementors@lists.cs.columbia.edu >https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors > _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
