We've a situation where tens or potentially hundreds of Contact addresses need to be bound to an AoR. Don't ask me why - it is an outcome of putting SIP in a large legacy switching system.
While allowed by SIP, it would seem somewhat awkward to send hundreds of Contact URIs in a SIP REGISTER message in a practical sense. Furthermore, it would be seriously detrimental to Registrar's performance if hundreds of UACs start sending hundreds of Contact URIs in their REGISTER messages all at once (for instance, at system start up). One way to solve this problem would be to pre-configure the Registrar with the Contact addresses using some out-of-band mechanism. The REGISTER message can then be used to turn the bindings on or off as opposed to carrying the bindings in it. Assuming that such an out-of-band mechanism for pre-configuring the Registrar exists, the question then would be what should we send in the Contact header in the REGISTER message. We could send one of the IP addresses from the Contacts set, but that's not really correct and a bit misleading. We could say that individual Contact groups are assigned their own domain name (e.g. sip:cgp100.com) and then carry that domain name in the Contact URI. We don't really have to or want to put these domain names in the DNS. It's basically a string that would identify which Contact group should be tied up to the AoR present in the To: header. You can assume that we control both the UAC and the Registrar and they are in sync with respect to what Contact URIs are present in each of these domain names. I'm not sure whether it makes to sense to use domain names in a Contact URI. The SIP ABNF allows it. Any thoughts or suggestions on this? -- Thanks, Raj Jain mailto:rj2807 at gmail dot com sip:rjain at iptel dot org _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
