Raj, I don't think this is a bug, the 200(REGISTER) must have a to tag per RFC3261.
Sec 8.2.6.2 If a request contained a To tag in the request, the To header field in the response MUST equal that of the request. However, if the To header field in the request did not contain a tag, the URI in the To header field in the response MUST equal the URI in the To header field; additionally, <NOTE>the UAS MUST add a tag to the To header field in the response</NOTE> (with the exception of the 100 (Trying) response, in which a tag MAY be present). This is the general UAS behavior, which definitely applies to registrar. fyi -Rockson -----Original Message----- From: Raj Jain [mailto:[EMAIL PROTECTED] Sent: Monday, November 24, 2008 7:40 AM To: Neelakantan Balasubramanian Cc: Bob Penfield; Rockson Li (zhengyli); Tarun2 Gupta; [email protected] Subject: Re: [Sip-implementors] Query regarding 'To' tag in REGISTER request On Fri, Nov 21, 2008 at 12:50 PM, Neelakantan Balasubramanian <[EMAIL PROTECTED]> wrote: > > Typically a REGISTER request doesn't not establish a dialog. RFC 3261 section 10.2. > > " A REGISTER request does not establish a dialog. A UAC MAY include a > Route header field in a REGISTER request based on a pre-existing > route set as described in Section 8.1. The Record-Route header field" > > Also from Section 8.1.1.2 > > A request outside of a dialog MUST NOT contain a To tag; the tag in > the To field of a request identifies the peer of the dialog. Since > no dialog is established, no tag is present. > > So, there is no need for a To tag in REGISTER. In order to have better interoperability, the presence of To tag should be ignored. Correct. I guess, one of the reasons why this confusion arises is due to the usage of To tag in REGISTER's 200 OK in RFC 3261 section 24.1. Historically, there was once a notion (when RFC 3261 was being written) that REGISTERs were dialog forming. Later, this idea was dropped, but the example wasn't scrubbed. This is probably captured as a bug at bugs.sipit.net. SIP/2.0 200 OK Via: SIP/2.0/UDP bobspc.biloxi.com:5060;branch=z9hG4bKnashds7 ;received=192.0.2.4 To: Bob <sip:[EMAIL PROTECTED]>;tag=2493k59kd From: Bob <sip:[EMAIL PROTECTED]>;tag=456248 Call-ID: [EMAIL PROTECTED] CSeq: 1826 REGISTER Contact: <sip:[EMAIL PROTECTED]> Expires: 7200 Content-Length: 0 -- Raj Jain _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
