Hi Paul, I agree that it isn't very clear; and I don't have strong opinion concerning how to interpret the text. However the RFC3261 snippet appears to apply to both Expires header and Contact parameter (at least associated with redirect server interactions). RFC2543 allowed SIP-date (absolute time) within both Expires header and Contact parameter which was the reason given for defaulting to 3600 upon receiving a malformed expires value.
Cheers, Brett > -----Original Message----- > From: [email protected] [mailto:sip- > [email protected]] On Behalf Of Paul Kyzivat > Sent: Wednesday, April 15, 2009 5:44 PM > To: Brett Tate > Cc: [email protected] > Subject: Re: [Sip-implementors] "Expires = \r\n" EQUALS "Expires = 0 \r\n" > - Is this right? > > I thought the inquiry was wrt the Expires header, not the expires header > parameter. The text in 8.3 seems to be talking about what to do if the > value of the expires parameter is malformed. And that only applies to > use in Contact, and perhaps only for use by redirect servers. > > So for instance I would argue that this doesn't apply to an Expires > header in a REGISTER. Or even to an expires parameter in a Contact > header in a REGISTER. > > (This section is not as clear as one might hope.) > > Thanks, > Paul > > So the > > Brett Tate wrote: > > RFC3261 section 8.3: > > > > "The "expires" parameter of a Contact header field value indicates how > long the URI is valid. The value of the parameter is a number indicating > seconds. If this parameter is not provided, the value of the Expires > header field determines how long the URI is valid. Malformed values > SHOULD be treated as equivalent to 3600. > > > > This provides a modest level of backwards compatibility with RFC 2543, > which allowed absolute times in this header field. If an absolute time is > received, it will be treated as malformed, and then default to 3600." > > _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
