to, 2008-06-19 kello 11:30 +0200, ext DRAGE, Keith (Keith) kirjoitti: > QUESTION 1 TO SIP WG: Are the use cases sufficiently important to > proceed with this draft? The document states: > > Chapter 3.5 of draft-ietf-sip-outbound-13 [I-D.ietf-sip-outbound] > defines two keep-alive techniques. Even though the keep-alive > techniques are separated from the Outbound mechanism > [I-D.ietf-sip-outbound], it is currently not possible to indicate > support of the keep-alive techniques without also indicating support > for the Outbound mechanism. > > The Outbound mechanism is enabled during the UA registration phase. > However, there are use-cases where the UA does not register itself, > but still needs to be able to make calls and maintain NAT bindings > open during the duration of that call. A typical example is > emergency calls. There are also cases where entities do not support > the Outbound mechanism, but still want to be able to indicate support > and use the keep-alive techniques defined in [I-D.ietf-sip-outbound]. > > At first sight this is not the most inspiring declaration of the need > for the document. Please respond indicating whether you consider this a > useful draft, and propose text that you think would be useful in this > section. Conversely, if you think this draft is not useful and the WG > has other more important things to work on first, please also respond.
In theory, there is a small, but valid, reason for the draft to exists. The draft could serve as a way to deploy outbound-aware proxies in front of outbound-unaware registrars, using UDP transport. However, arguably UDP is deployed and works through NAT today, which is why I find it unlikely that anyone would deploy outbound keepalives in this way. > QUESTION 2 TO SIP WG: Do we have a robust set of requirements for > proceeding with this work? The document currently lists: > > REQ 1: It MUST be possible for a UA to indicate support of the keep- > alive techniques defined [I-D.ietf-sip-outbound] if the UA supports > only the keep-alive part of [I-D.ietf-sip-outbound]. > > REQ 2: It MUST be possible for an edge proxy to indicate support of > the keep-alive techniques defined [I-D.ietf-sip-outbound] if the edge > poxy supports only the keep-alive part of [I-D.ietf-sip-outbound]. > > It would be desirable to agree these at the outset, and not revisit them > if we continue with the work. So if you require clarification, > modification, or addition to these two requirements, then please also > response with your questions and proposals. These requirements would make sense, but iff there was an actual need to have this ability in the first place, as I described above. I don't think such a need exists in practice. (Note, this upgrade path only exists for UDP; for TCP registrars need to be outbound-aware.) Cheers, Aki _______________________________________________ Sip mailing list https://www.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
