Subject: [Sip] Re: [Sipping] Tags in respones to CANCEL WAS: Re: Question about Section 3.8 ofdraft-ietf-sipping-basic-call-flows-01.txt(Eiji Tomimura)

From: Jiri Kuthan <[email-masked]>
Date: Fri, 08 Nov 2002 18:54:26 +0100

I think neither choice could harm interoperability and none of the
cons/prons is a particularly strong argument. All in all, to-tags 
are primarily used to establish a dialog and when a CANCEL is processed, 
the dialog is destroyed before ever set up. 

My esthetic preference is "YES" too -- just to avoid special-casing.

It it primarily a clarification issue. The text was making some people
believe that proxy servers had to guarantee to-tags in their replies
to CANCELs equal to to-tags in replies to cancelled INVITE.

Thanks,

-Jiri

At 04:34 PM 11/5/2002, Gonzalo Camarillo wrote:
>Hi,
>
>Let's try to finish this discussion. Summarizing:
>
>Should the 200 OK responses to CANCEL have a To tag?
>
>Reasons for NO:
>
>CANCEL is hop-by-hop, and therefore, 200 OK responses for CANCEL are
>also hop-by-hop. If we look at 100 Trying responses, which are
>hop-by-hop as well, we see that they do not have a tag.
>
>Reasons for YES:
>
>Final responses to any request have tags. Even non-2xx final responses
>for INVITE, which are hop-by-hop, have a tag.
>
>Note that user agents and proxies will have to be prepared to receive
>200 OK responses for CANCEL with or without tags anyway, to improve
>interoperability. So, this is not a big deal after all. Our decision is
>only useful as long as it helps develop a coherent spec.
>
>
>I would suggest to go for YES, document it, and move on.
>
>Comments?
>
>Thanks,
>
>Gonzalo 

_______________________________________________
Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
This list is for NEW development of the core SIP Protocol
Use [email-masked] for questions on current sip
Use [email-masked] for new developments on the application of sip