There is no standard way of doing this and there are many options as long as the UA and the IP-PBX agree upon on it. One simple option would be to use the reason header in the Cancel Message which the UA can use to distinguish why the Request is cancelled and do the necessary clean up.
Kasturi On Wednesday 12 April 2006 05:29, 이성우 wrote: > Dear, > > I am implementing a Group Ring facility in a small-sized IP-PBX system that > uses 3 user agents internally. I wonder how I can mark a group ring INVITE > message to differentiate other normal INVITE message? This is for clearing > 'missied call' log at all other user agents except for the one that > actually received the call. > > Current Scenario is as followings. > > 1. Each user agent in IP-PBX system is set to a group ring function. > 2. There comes a SIP INVITE message from outside to IP-PBX system. > 3. IP-PBX system forwards the INVITE message to each user agent that are in > the same ring group. 3. Each 3 user agent makes a ring responding 180 > message each. > 4. One user agent receives and send 200 OK back to the caller (IP-PBX > system). 5. Now that IP-PBX knows it received an answer from a user agent, > it sends CANCEL to other user agents. 6. Each of the 2 user agents process > the CANCEL message leaving 'missed call' log in its LCD window. > > > > Caller UA IP-PBX UA1 UA2 UA3 > > | INV | | | | > |----------------->| INV | | | > | > | |--------------->| | | > | | INV | | | > | |----------------------->| | > | | INV | | | > | |------------------------------>| > | | 180 | | | > | |<---------------| | | > | | 180 | | | > | |<-----------------------| | > | | 180 | | | > | |<------------------------------| > | | 200 | | | > | |<---------------| | | > | | ACK | | | > | |--------------->| | | > | | CANCEL | | | > | |----------------------->| | > | | CANCEL | | | > | |------------------------------>| > > My questions are > Q1. How can I let the user agents know that the incomming INVITE message is > group-call? Q2. If I use a specific SIP Header in the INVITE message (from > IP-PBX to UAs) to carry the group-call infomation, what header should I use > and how? > Q3. Can I use the specific SIP Header in CANCEL message instead of INVITE > for the same purpose? > > Thanks in Advance. > > > > Lee, Sungwoo > > OfficeServ Development/VoIP > Telecommunication System Div. > Samsung Electronics Co., LTD. > > [EMAIL PROTECTED] > TEL: 82-31-279-4329 > FAX: 82-31-279-2296 > Mobile: 82-10-3015-4329 > > _______________________________________________ > Sip-implementors mailing list > [email protected] > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
