> -----Original Message----- > From: Dean Willis [mailto:[EMAIL PROTECTED] > Sent: Tuesday, October 02, 2007 11:47 AM > To: Stucker, Brian (RICH1:AR00) > Cc: Adam Roach; Barnes, Mary (RICH2:AR00); [email protected] > Subject: Re: [Sip] INFO > > > On Oct 1, 2007, at 3:01 AM, Brian Stucker wrote: > > > > > So if we're allowing SIP-T, which builds off of a baseline SIP > > requirement that if you get a MIME type or method (INFO) that you > > don't understand, that you gracefully handle this: send a > 415/488 or > > send a 405, respectively, then why are we disallowing other uses of > > INFO that do not introduce ANY requirements beyond those of SIP-T > > which we are allowing? > > > > This raises the argument that SIP-T should be revisited to > more clearly negotiate support for the material being > tunneled, including the context in which it is being > tunneled. My UA might, for example, know how to render an > ISUP message using a pretty-printer. That doesn't mean it > knows how to do SIP-T for gateways. > > So, SIP-T is broken and likely to give surprising results. > That is not a hearty argument for endorsing the technique of > SIP-T for other functions.
Nor is it a hearty argument for clarifying what's wrong with INFO by allowing it. > > > > Here's another question for the readers: let's say Eric's draft > > becomes an RFC as written for sake of argument. What > happens when a UA > > that does not support SIP-T gets a call from an ISUP > gateway and gets > > an INFO with encapsulated ISUP in the message body? How does this > > processing differ from an endpoint getting encapsulated DTMF in a > > format it may not understand? It doesn't differ because it > can't: the > > UA cannot differentiate between two different MIME types > when it does > > not recognize either of them. > > But assume the UA DOES recognize the MIME type. How does it > know what to do with it? Is content-disposition adequate? Depends on how it recognizes it to my mind. I recognize you when I see you, and I recognize my 5-month old son when I see him, but I don't need a sticky on your foreheads to tell me how I should interact with you. If we're saying that everything about how a UA handles a MIME type has to be meticulously stipulated in the signaling, then I think there's a lot more out there that's broken than INFO. Basically, you wouldn't be able to introduce any MIME type into your signaling assuming that the other end will gracefully deal with it if it doesn't know what to do with it. How many MIME types are out there and how many of them have been specifically specified as to how SIP works with them? > > If it were, why would we have the higher-level negotiation of > event contexts? There's a lot more to events than specifying a MIME type. Do they have to be signaled distinctly in order to be useful? Should the accept header be deprecated? > > -- > Dean > > > _______________________________________________ Sip mailing list https://www1.ietf.org/mailman/listinfo/sip This list is for NEW development of the core SIP Protocol Use [EMAIL PROTECTED] for questions on current sip Use [EMAIL PROTECTED] for new developments on the application of sip
