Hi, CANCEL is a hop-by-hop req, the to tag is used to identify the UAS that is responding,
So if CANCEL passes through a stateful proxy , the to tag of 200(CANCEL) and final response for cancelled req are Probably different. Rockson -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of I?aki Baz Castillo Sent: Thursday, August 21, 2008 6:19 AM To: [email protected] Subject: [Sip-implementors] Why 200 for CANCEL needs "To tag" different whenproxy or UAS Hi, when a UAS receives a CANCEL it must generate a 200 OK for that CANCEL with the same "To tag" that te one in the 487 that terminates the INVITE transaction. But when a proxy receives a CANCEL the "To tag" in the 200 OK mustn't match the "To tag" in the 487. Since CANCEL is matched as transaction layer (no need for dialogs) I just can't understand why is needed a "To tag" in the 200 OK for a CANCEL. Also, I can't understand why different requeriments for UAS core and proxy core. IMHO this is one of the typical hyper-redundant issues that make SIP excesively complex with no reason. :( -- Iñaki Baz Castillo _______________________________________________ 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
