El Jueves, 29 de Enero de 2009, Johansson Olle E escribió: > 28 jan 2009 kl. 16.22 skrev Victor Pascual Ávila: > > We chose not using the REFER basically 'cause, at that moment, REFER > > was not implemented in many UAs. However, the 72% of the UAs tested > > during the last SIPit implemented the REFER method. > > I do like this method too, and is a bit surprised that I haven't seen > any requests for that > support in Asterisk. Only one customer has asked for it, but did not > want to fund the work > to create that functionality.
I was thinking yesterday on it. REFER initial-dialog is much cleaner than INVITE of 3PCC, but it's usually not allowed by common phones. So a PBX or SIP server implementing click2dial could try first a REFER initial-request, and in case it receives a negative response (i.e. "403 Forbidden" or "501 Not Implemented") the the server could use the 3PCC INVITE. > And I'm not sure that all of those 72% supported REFER outside of a > dialog, as a way to > create a dialog. Was that documented? I've tryed it with some common phones with no luck. The problem is that desktphone don't ask permission to the user when receiving a typical in-dialog REFER, so in those phones allowing initial REFER would be a great risk. -- Iñaki Baz Castillo _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
