<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><DIV>Hi Klaus,</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>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 :-(</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>I think this request should land on the IETF sip mailing lists and I would be happy to back it up.</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Adrian</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>>>>>>>>>>></DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">Hi!</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 11px/normal Courier; min-height: 10px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">This is a little bit OT, but maybe you can help me out. Consider the</SPAN></FONT><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"> </SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">following setup: I have a SIP service running on mydomain.com.</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 11px/normal Courier; min-height: 10px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">My sip AoR is sip:</SPAN></FONT><A href="http://lists.iptel.org/mailman/listinfo/serusers"><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"><FONT class="Apple-style-span" color="#0050DC">klaus at mydomain.com</FONT></SPAN></FONT></A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 11px/normal Courier; min-height: 10px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">mydomain.com resolves to my main SIP proxy (registrar, proxy, used by</SPAN></FONT><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"> </SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">all local clients) using NAPTRs, SRV and A records.</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 11px/normal Courier; min-height: 10px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">Further, I do want to have a separate proxy (edge proxy) which handles</SPAN></FONT><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"> </SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">signaling from/to external domains, TLS, white/blacklisting ....</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 11px/normal Courier; min-height: 10px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">Thus, the domain mydomain.com should resolve to:</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">- the main proxy for SIP clients</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">- the edge proxy for SIP proxies</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 11px/normal Courier; min-height: 10px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">Of course I could use different domains or the clients have to configure</SPAN></FONT><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"> </SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">an outbound proxy (which points directly to the main proxy), but this</SPAN></FONT><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"> </SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">complicates configuration.</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 11px/normal Courier; min-height: 10px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">AFAIK, Microsoft solved this problem within the LCS using different</SPAN></FONT><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"> </SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">prefixes during the SRV lookup. The Live Communicator (client) uses</SPAN></FONT><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"> </SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">_sipinternal._udp.mydomain.com to find the main proxy, whereas the LCS</SPAN></FONT><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"> </SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">uses _sip._udp.domain.com to find the edge proxy (access proxy in</SPAN></FONT><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"> </SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">Microsoft terms) of mydomain.com.</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 11px/normal Courier; min-height: 10px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">Thus, I would like to raise discussion: Have you an idea how to solve</SPAN></FONT><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"> </SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">this? Are you aware of any RFCs/drafts addressing this problem?</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 11px/normal Courier; min-height: 10px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">regards</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;">klaus</SPAN></FONT></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><FONT class="Apple-style-span" face="Courier" size="3"><SPAN class="Apple-style-span" style="font-size: 11px;"><BR class="khtml-block-placeholder"></SPAN></FONT></DIV></BODY></HTML>