El Miércoles 08 Abril 2009, Paul Kyzivat escribió: > "forget negotiation". Look at the base note of this thread. The guy > needs a way to negotiate between INFO and 2833. > > Our products support 3 or 4 ways of sending DTMF. And ad hoc means of > negotiating among them have been developed. > > Normally you don't want the DTMF both places, because that causes its > own set of problems. Somebody instead filters the dtmf out of the media > and puts it in the signaling. We have very common situations where one > side has it in media and the other side needs it in signaling. During > call setup we have to figure out whether to put in a media relay to > convert between the two, or if we can omit that.
Good reasons, you are right. For example there are phones sending DTMF in both SIP INFO and RFC2833 at the same time. How should react a UAS receiving both? which one to filter? the first arriving? > > Ok, let's make complex something so easy as DTMF. Now the solution for > > DTMF is KPML with lot of exotic XML and so on. Great, sure it will > > inmediatelly adopted by most of the vendors and implementation, sure. > > In retrospect, perhaps KPML was over engineered. If so, then it will not widely implemented. Vendors don't like complex mechanisms. :( Thanks. -- Iñaki Baz Castillo <i...@aliax.net> _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
