Hi Paul, According to your response as below. "It is also possible for Alice to use 3pcc O/A techniques to establish a direct *media* path between Bob and Charlie, while Alice remains in the signaling path between them"
While Alice remains in the signaling path means it is some thing like "Conference Call you are talking about" Correct me if i am wrong. Thank you, With Regards Arun A. Tagare On Wed, Aug 6, 2014 at 12:30 AM, Sourav Dhar Chaudhuri < sourav_mi...@yahoo.co.in> wrote: > Hi Paul, > Thanks a lot for your detailed response. You have answered all my > doubts. > > I am really grateful for your email. > > Thanks & Regards, > Sourav Dhar Chaudhuri > > > > On Tuesday, 5 August 2014 8:11 PM, Paul Kyzivat <pkyzi...@alum.mit.edu> > wrote: > > > > On 8/4/14 10:12 AM, Sourav Dhar Chaudhuri wrote: > > Hi, > > Is there any way when a answered call [ 200OK is already provided > for initial INVITE and ACK also sent] can be transferred without using > REFER method? > > > > If it is possible without REFER then please let me know required > procedure. > > More detail is needed to answer this. > > Lets assume that Alice and Bob are in a call. You want a transfer, so > let's assume the transfer target is Charlie. > > Further, assume it is Alice that wants to initiate the transfer, > resulting ultimately in Bob talking to Charlie. > > A simple answer to your question is for Alice to initiate the call to > Charlie, and then bridge the media between Bob and Charlie. It is also > possible for Alice to use 3pcc O/A techniques to establish a direct > *media* path between Bob and Charlie, while Alice remains in the > signaling path between them. > > The reason for REFER is to get Alice out of the signaling path. If there > is a middlebox in the signaling (e.g. a sip pbx or an SBC) then in > principle Alice can ask that middlebox to handle the transfer. But Alice > needs a way to convey the desire to do so. Often REFER is still used for > that, but is intercepted by middlebox, which then uses mechanisms such > as I described above. Some other mechanism, other than REFER, can be > used for that but it will be a proprietary solution. > > Does that help? > Paul > > > > > _______________________________________________ > Sip-implementors mailing list > Sip-implementors@lists.cs.columbia.edu > https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors > _______________________________________________ > Sip-implementors mailing list > Sip-implementors@lists.cs.columbia.edu > https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors > -- With Regards Arun A. Tagare +91 9449 029729 _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
