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
