Hi Iñaki, in my scenario it works as follows. On Wed, Jan 28, 2009 at 3:58 PM, Iñaki Baz Castillo <[email protected]> wrote: > Hi, RFC 3725 "Best Current Practices for Third Party Call Control > (3pcc) in SIP" defines a way to create third party calls by sending an > INVITE to both, the caller and the callee. > > I don't like it at all, it seems not ellegant hack IMHO: > > - Alice uses a Click2Dial web page to call Bob.
These are actually HTTP/SOAP requests > - The web server generates an INVITE which arrives to Alice's phone and so... The B2BUA generates the initial invite (no SDP) towards Alice; Alice sends a 200 OK (SDP1) The B2BUA generates an invite (SDP1) towards Bob; Bob sends a 200 OK (SDP2); B2BUA sends ACK towards Bob and ACK(SDP2) towards Alice. > This means that this call will appear in the phone call list as a > *received* call, when the *real* concept is that it's an outgoing call > (from Alice's point of view). How does your "call list" work? In some cases, when the B2BUA sets the from header field to Alice, it appears as an outgoing call. > So I prefer the simple initial-request REFER approach already defined > in RFC 3515 (REFER method) but I do know that it's not implemented in > most of the phones. Perhaps I'm wrong? is it implemented somewhere? If > not... why? It seems a really ellegant and clean solution. 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. Cheers, -- Victor Pascual Ávila _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
