I guess the proxy/registrar will/should *not* be maintaining any information residing in the REGISTER request, except, of course, the From (excluding tag), Contact & Expires fields.
The tag parameter is actually significant when there is a possibility of 2 or more REGISTER requests, from different sources, having the same call-id, arriving at a proxy at the same time. In this case, however, once the first REGISTER is executed, the proxy forgets about the dialog, and thus the next request will be treated as a new/update request and it will update the registration expiry time. Sharad -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Prakash GS Sent: Tuesday, July 02, 2002 11:23 AM To: [EMAIL PROTECTED] Cc: Nirmalya (E-mail) Subject: [Sip-implementors] Refreshing Registration query Hi all I have a doubt regarding a refreshing registration. Assume that a User-Agent A has registered using the following REGISTER message with a proxy+registrar. REGISTER sip:proxy.com SIP/2.0 Via:SIP/2.0/UDP ua1:5060 From:<sip:3251@ua1;User=phone>;tag=278100000000000000000715 To:<sip:3251@ua1;User=phone> Contact:<sip:3251@ua1;User=phone> Call-ID:01B2270D4881400000000000@ua1 CSeq:1 REGISTER Expires:180 A goes down and comes up again. It attempts to register and sends a registration with the SAME call-id and Cseq as before but with a DIFFERENT tag in the From header . How should the proxy treat the REGISTER and why ? Should it : (a)Consider the REGISTER as a retransmission from A or (b)Should it keep track of the 'Tag' and so treat the request as a new REGISTER ? In essence what is the role of the 'Tag' field in such a scenario, if any ? Thanks Prakash GS _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
winmail.dat
Description: application/ms-tnef
