El Lunes, 11 de Mayo de 2009, Dale Worley escribió: > On Sat, 2009-05-09 at 10:05 +0530, Vivek Batra wrote: > > Moreover, does this mean that an Operator initiating Attended Transfer > > cannot free-up herself since the transfer target is not responding? > > This would be very taxing in practical world because most of the > > times, the Operator wishes to execute Attended Transfer but since the > > transfer target does not respond in time, she frees up herself (by > > performing the Attendant Transfer activity in ringing state) for > > receiving other calls. > > > > What is the way out? > > In practice, the solution is for the user agent to perform the transfer > in the background by doing nothing until the new call leg is answered, > and then sending the REFER that completes the transfer. (This has been > understood since at least 2003, when the Pingtel Xpressa phone > implemented it.) Although the phone must perform much activity, the > user of the phone is freed to do other things.
Interesting. And does some phone implement it? (I've never seen it). IMHO this mechanism is really poor. The phone is using a line until the transfer target answers the call. What about simple phones with just 2 lines? How to explain the human user that a phone line is still busy even if he has already free-up himself? This is a really bad design IMHO, and it's obvious why so many vendors have decided not to implement it. Regards. -- Iñaki Baz Castillo <[email protected]> _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
