I am becoming concerned that we are now at this late stage going into requirement inflation. This appears to be such.
I do not remember a requirement to provide redundant connections to registrars as amongst the original requirements. 1. Must be able to detect that a UA supports these mechanisms. 2. Support UAs behind NATs. 3. Support TLS to a UA without a stable DNS name or IP address. 4. Detect failure of a connection and be able to correct for this. 5. Support many UAs simultaneously rebooting. 6. Support a NAT rebooting or resetting. 7. Minimize initial startup load on a proxy. 8. Support architectures with edge proxies. Regards Keith > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of Dean Willis > Sent: Tuesday, October 07, 2008 11:17 PM > To: Paul Kyzivat > Cc: [email protected]; Christer Holmberg > Subject: Re: [Sip] Dual registration without Outbound > > > On Oct 7, 2008, at 3:37 PM, Paul Kyzivat wrote: > > > I think I am missing something here. I presume that the > knowledge of > > the UA is limited to: > > - to proxy addresses > > - an AOR to register > > > > Presumably the address of the registrar is derived from the AOR to > > register by removing the user part. So the UA, when registering, > > doesn't specify two different registrars. Whether there are > two or not > > is a function of how the proxy routes the register request. > So whether > > the two registers for the same contact go to one registrar > or two is > > unknown to the UA. In some configurations this would give you > > redundancy, and in others it would not. > > > > Then, what causes the UA to register two different > contacts? Are the > > wlan contact and the 3g contact registered to *different* > AORs? If not > > I don't see the point. If anything, I would expect that 3g and wlan > > represent access networks and hence differing proxies, not AORs or > > registrars. > > > > Some IMS networks have mechanisms for discovering the edge > proxy based on the air interface. This, a UA might discover > one proxy for its 3g interface, and another for its WLAN > interface. In other words, one proxy for each Contact. > > So, that's "proxy" discovery. > > Registrar discovery is a separate process. With > config-framework, the UA is configured with a set of proxies > with which it may register. > Under outbound-015, if there are two or more outbound proxies > in the configured set, the UA must register through at least > two of those proxies. This assumes a singular contact at the UA. > > Juha has, IIRC, proposed that the UA must register with at > least two of those proxies for each contact. This, I believe, > has some merit. > I'm not sure it's a MUST, but it certainly seems a reasonable SHOULD. > > Of course, when the configuration mechanism is different and > only one proxy is provided per contact, we have a different case. > > It seems like we are developing two conflicted use cases here > -- one for a singular contact with redundant registration > paths, and another for redundant contacts, each with singular > registration path. > > Then there may be yet another case, multiple contacts, each > with redundant registration paths. > > -- > Dean > > _______________________________________________ > 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 > _______________________________________________ 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
