On 05/12/2012 14:12, Kevin Fleming wrote: > I suppose it could choose to unregister and re-register in some other way > in order to achieve its goals of receiving FAX calls, if it was configured > with enough network information to do so. > > Now that I think about it some more, is a registrar even allowed to return > a Contact header that differs from the one the UA supplied in its REGISTER > request? I suspect this is *not* allowed, and so if the registrar supports > Caller-Pref but the specific tag(s) in question fail some sort of > validation process, its only recourse would be to fail the REGISTER request > with a suitable error response.
If that's the standard behaviour, it would of course answer my question. Brian > > > On Wed, Dec 5, 2012 at 6:35 AM, Brian E Carpenter < > [email protected]> wrote: > >> On 05/12/2012 11:01, Kevin Fleming wrote: >>> The language in RFC 3840 doesn't appear to contemplate the situation >> you've >>> proposed. In its world, registrars can either support prefs (and will >>> accept "Require: pref") or they don't, and they don't have knowledge of >>> which feature tags are registered with IANA and which are not. Of course, >>> they *coud* attempt to validate the tags expressed by the UA, but I don't >>> see an explicit way for the registrar to indicate that the UA included >>> disallowed tags in its request. >> Understood, but in that case I don't see what good the confirmation >> of the tag from the registrar to the UA achieves - the UA is not going >> to be able to do anything with it (except maybe log whether it was >> received). >> >> Brian >> > _______________________________________________ Gen-art mailing list [email protected] https://www.ietf.org/mailman/listinfo/gen-art
