> -----Original Message----- > From: Scott Lawrence [mailto:xmlscott@xxxxxxxxx] > Sent: Thursday, April 08, 2010 9:37 AM > To: Hadriel Kaplan > > Well, one could argue that a provider could cause the returned SIP url > for the change notice subscription to be one for which there is no > routing (return 'Link: <sip:devnull.example.org>'). By the rules, the > UA would periodically make a DNS request to try to find it, but would be > allowed to use the configuration data. Silly, but allowed. Right, but the since that would make it an "unknown validity" config, and the requirements do not mandate any UA to *use* an "unknown validity" config... do you see a problem? Instead of getting into an unknown-behavior state, why don't you simply allow the HTTP response to NOT have a Link header, or define a NULL URI to use - and then state that it means there is no Subscription service and the UA MUST consider the HTTP-based config valid? > No one is going to be forced to use any of this specification. If you > don't want the features it provides (automatic initial configuration > with prompt updates), then don't use it. So we should go define another profile which is a textual copy of this one, but changes two sentences?? Is that really good for SIP or the SIP-Forum? > At the risk of repeating myself, I want to make sure that one reason for > using SUBSCRIBE/NOTIFY for the change notices is clear: there is no > other existing standard way to address a specific User Agent. Right, I understand that you have no other way to do X. Fine, so specify how to do X. Don't mandate that X be used with Y, when Y does not depend on X to function properly, and X is not trivial. -hadriel _______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf