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.
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
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
AFAIK, Microsoft solved this problem within the LCS using different
prefixes during the SRV lookup. The Live Communicator (client) uses
to find the main proxy, whereas the LCS
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?