Hi Aswin, Actually annexb=yes|no is an optional parameter. So many phones may not support it. It is mainly used to indicate if voice activity detection is used or not.
So in your case you should not be rejecting the call, because there is no way you can know if the incoming codec supported is g729a or b. Regards Ranjit -----Original Message----- From: Aswin Bhupalam [mailto:[EMAIL PROTECTED] Sent: Tuesday, July 19, 2005 12:03 PM To: Avasarala Ranjit-A20990; [email protected] Cc: Sushil \\(E-mail\\); Uttam Kumar Sarkar Subject: Re: [Sip-implementors] G 729 a & b negotiation Hi Ranjit, Thanks for the quick reply. My code has a default of g.729b as per rfc 3555. But, many phones are sending codec "18" with out any annexb param in "a=" line, so we are rejecting the call as we are not supporting g.729b. Is this correct behaviour? Regards, Aswin Bhupalam. ----- Original Message ----- From: "Avasarala Ranjit-A20990" <[EMAIL PROTECTED]> To: "Aswin Bhupalam" <[EMAIL PROTECTED]>; <[email protected]> Cc: "Sushil \(E-mail\)" <[EMAIL PROTECTED]>; "Uttam Kumar Sarkar" <[EMAIL PROTECTED]> Sent: Tuesday, July 19, 2005 11:52 AM Subject: RE: [Sip-implementors] G 729 a & b negotiation > Hi > Parameter annexb=yes|no as defined in RFC 3555 can be used to indicate > if the codec supported is G.729a and G.729b > > So the complete SDP should be > > v=0 > o=root 743184990 743184990 IN IP4 10.50.10.146 s=call c=IN IP4 > 10.50.10.146 t=0 0 m=audio 10014 RTP/AVP 18 101 > a=rtpmap:18 g729/8000 > a=fmtp:18 annexb=yes > a=rtpmap:101 telephone-event/8000 > a=fmtp:101 0-15 > a=ptime:20 > a=sendrecv > > Regards > Ranjit > > > > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Aswin > Bhupalam > Sent: Tuesday, July 19, 2005 10:47 AM > To: [email protected] > Cc: Sushil \(E-mail\); Uttam Kumar Sarkar > Subject: [Sip-implementors] G 729 a & b negotiation > > All, > say "a=" line is not having 'annexb' parameter, which one(g729a or > g729b) should we take as default. > > Snom phone sends an INVITE with the following SDP: > > v=0 > o=root 743184990 743184990 IN IP4 10.50.10.146 s=call c=IN IP4 > 10.50.10.146 t=0 0 m=audio 10014 RTP/AVP 18 101 > a=rtpmap:18 g729/8000 > a=rtpmap:101 telephone-event/8000 > a=fmtp:101 0-15 > a=ptime:20 > a=sendrecv > > Which codec is being negotiated here?(g729a or g729b) > > Dave, > I found your mail regarding the same question. > kindly let me know if you've found something useful. > > Regards, > Aswin Bhupalam. > > -----Messaggio originale----- > Da: sip-implementors-bounces at cs.columbia.edu > [mailto:sip-implementors-bounces at cs.columbia.edu] Per conto di > David Stuart > Inviato: giovedì 8 luglio 2004 20.10 > A: sip-implementors at cs.columbia.edu > Oggetto: [Sip-implementors] g729 annex B negotiation > > Hi All, > > What is the correct way to negotiate annex B when using g.729 (as > opposed to > A)? They both use the same payload type, 18. > > I see two different mentions of this, RFC 3555 section 4.1.9, and RFC > 3108 sec 5.6.3.2 but they seem to be saying different things. > > Can anyone point me to the correct example as to how to achieve this? > > -- > David Stuart, SIPquest > Email: dave (at) sipquest (dot) com > Phone: 254-8886 x234 Web: http://www.sipquest.com/ > Address: 106 - 350 Terry Fox Drive, Kanata Ontario, K2K 2P5 > > > > _______________________________________________ > Sip-implementors mailing list > [email protected] > http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
