Hi Klaus,

Your question is so legitimate that both sip device manufacturers including Msoft and Xten (they use _outbound._xxx) and those who operate live deployments try to find a legitimate solution for it. IETF is a bit busy now with building IMS :-(

I think this request should land on the IETF sip mailing lists and I would be happy to back it up.

Adrian

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Hi!

This is a little bit OT, but maybe you can help me out. Consider the following setup: I have a SIP service running on mydomain.com.

My sip AoR is sip:klaus at mydomain.com

mydomain.com resolves to my main SIP proxy (registrar, proxy, used by all local clients) using NAPTRs, SRV and A records.

Further, I do want to have a separate proxy (edge proxy) which handles signaling from/to external domains, TLS, white/blacklisting ....

Thus, the domain mydomain.com should resolve to: - the main proxy for SIP clients - the edge proxy for SIP proxies

Of course I could use different domains or the clients have to configure an outbound proxy (which points directly to the main proxy), but this complicates configuration.

AFAIK, Microsoft solved this problem within the LCS using different prefixes during the SRV lookup. The Live Communicator (client) uses _sipinternal._udp.mydomain.com to find the main proxy, whereas the LCS uses _sip._udp.domain.com to find the edge proxy (access proxy in Microsoft terms) of mydomain.com.

Thus, I would like to raise discussion: Have you an idea how to solve this? Are you aware of any RFCs/drafts addressing this problem?

regards klaus