On 12.12.18 at 19:43 Joshua C. Colp wrote: > On Wed, Dec 12, 2018, at 12:31 PM, Michael Maier wrote: > > <snip> > >> >> The problem: The extension doesn't create a ringback locally, because >> it most probably expects it to >> be sent by the callee - but the callee doesn't send anything (not >> surprising, because there has been >> no SDP). >> >> Or should Asterisk create the ringback (Asterisk doesn't send any RTP >> package)? Or should the phone >> create the ringback itself because there is a 180 Ringing (even if it >> contains SDP)? >> >> I'm wondering: Why does Asterisk create a 183 to the extension >> containing SDP if the callee didn't >> provide any SDP? >> >> >> So many questions ... . Could somebody please shine some light on it? >> What's going wrong here? > > The core doesn't communicate whether progress includes media or not, so the > PJSIP channel driver (and even chan_sip) assumes media is there.
Another question: is there any use case for 183 Session Progress w/o SDP? IOW: Is a 183 Session Progress just a bug of the ISP? If so, problem could be solved by dropping each 183 package w/o SDP. Thanks, Michael -- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- Check out the new Asterisk community forum at: https://community.asterisk.org/ New to Asterisk? Start here: https://wiki.asterisk.org/wiki/display/AST/Getting+Started asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
