Subject: [Sip] RFC 3515, RFC 4508, RFC 3261: angle bracket requirement

From: "Brett Tate" <[email-masked]>
Date: Fri, 7 Dec 2007 11:08:16 -0500

The following rfc3261 section 20 text defines when a name-addr must be
used instead of an addr-spec.  However the text currently does not
appear generic enough to apply to all headers.

RFC 3261 section 20: "The Contact, From, and To header fields contain a
URI.  If the URI contains a comma, question mark or semicolon, the URI
MUST be enclosed in angle brackets (< and >).  Any URI parameters are
contained within these brackets.  If the URI is not enclosed in angle
brackets, any semicolon-delimited parameters are header-parameters, not
URI parameters."

RFC 3515 does not mention the rfc3261 rules.  RFC 4508 only mentions the
parameter impacts.

Does the rfc3261 rule concerning comma and question mark apply to the
refer-to header?  

Does the rfc3261 rule apply to all sip headers defined as containing
name-addr or addr-spec?  And if so, should the text be update per
sip-essential-correction process?

If comma and question mark aspects of the rfc3261 text is not relevant
Refer-To, what is reason for the difference?

Thanks,
Brett

_______________________________________________
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

---

From: Robert Sparks <[email-masked]>
Date: Fri, 7 Dec 2007 08:21:07 -0800

That language is intended to apply to any uses of name-addr.
There's a closely related bug captured already: http://bugs.sipit.net/ 
show_bug.cgi?id=765

RjS

---

From: [email-masked]
Date: Tue, 11 Dec 2007 12:56:05 -0500

From: "Brett Tate" <[email-masked]>

The shortest statement of the real rule is "In locations where the
grammar allows either name-addr or addr-spec to appear, the following
restriction applies:  If the URI contains a comma, question mark or
semicolon, the name-addr form must be used."  This rule covers all
extension headers, etc., because it is necessary to disambiguate
"name-addr / addr-spec".

As you can see from section 2.1 of RFC 3515, Refer-To allows both
name-addr and addr-spec and so is subject to this disambiguation rule.

I've overstated things above -- the restriction is needed to
disambiguate appearances of semicolon.  The restriction in regard to
comma is needed to disambiguate uses of addr-spec in lists.  The
restriction in regard to question mark doesn't seem to be needed for
disambiguation -- I wonder why it's there.

Dale