To show what kind of events values (RFC2833 DTMF) a UA can receive it "may" send a attribute a=fmtp:101 0-15,66,70. As I understand, if a AU receives this information from the remote side in an invite, this UA doesn't have to add a fmtp in the 200 OK if it only can receive 0-15 (since this is mandatory)? Is this a valid scenario:
>From A in invite: a=fmtp:101 0-15,66,70 >From B in 200 OK: No fmtp attribute. In the call above, A and B will send dtmf using rfc2833 for 1-15? If AU initiate a call and wants to use rfc2833 dtmf for format 1-15, it should be enough to have: m=audio 7000 RTP/AVP 0 8 101 a=rtpmap:0 PCMU/8000 a=rtpmap:8 PCMA/8000 a=rtpmap:101 telephone-event/8000 Sending this media description above will indicate for the remote side that I want to use out of band dtmf according to rfc2833 and I can receive dtmf events 0 to 15? This means it is no need for me to add fmtp if I only support events 1-15? Regards, // Andreas _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
