>> I still think that there should be a difference between: >> * I can't help you and no one can (e.g. user is not online - 404) >> * I can't help you do to some temporary issue (network - 503 or otherwise >> - 480) >> * I can't help you but feel free to try elsewhere (e.g. cannot find a >> route to the target do to one of many reasons) > I thought that the last category *is* what a 404 is for, while the first category is a 604. So I always understood the difference between these two to be that a 404 indicated more of a "temporary" problem (i.e. user is valid but not online) as in fact a Retry-after can be added to a 404, while a 604 was more of a permanent problem (i.e. no such user) - not exactly what I was looking for. > (well, I assume you don't actually mean "cannot find a route to the target" for the last category - because that is what a 480 is for :) My problem with the 480 is the "temporary" aspect associated with it which implies that there is a point in trying again (possibly after a Retry-after interval). In cases where I cannot route your request not due to network capacity issues (5xx) but due to the lack of the necessary commercial relationships - I do not see how this header is appropriate. > It's kind of a bold statement to say "I know you can't reach this user by any means anywhere", when the URI is an E.164 number. I wasn't really referring to E164 with regard to 404 - more of registry based AORs. _______________________________________________ Sipping mailing list https://www.ietf.org/mailman/listinfo/sipping This list is for NEW development of the application of SIP Use sip-implementors@xxxxxxxxxxxxxxx for questions on current sip Use sip@xxxxxxxx for new developments of core SIP
