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<TITLE>looping back calls</TITLE>
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<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New">Hi,</FONT></SPAN></P>
<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New">I saw this link in voip-info wiki site,</FONT></SPAN></P>
<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New"><A HREF="http://voip-info.org/wiki-Asterisk+at+large">http://voip-info.org/wiki-Asterisk+at+large</A></FONT></SPAN></P>
<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New">Quote,</FONT></SPAN></P>
<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New">I don't think that Asterisk is quite ready to support all live</FONT> <FONT SIZE=2 FACE="Courier New">deployment scenarios that include a 3rd party SIP proxy.</FONT> <FONT SIZE=2 FACE="Courier New">One problem I ran into was Asterisk does not handle looped back calls. </FONT></SPAN></P>
<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New">For example a call comes in over PSTN to Asterisk, Asterisk forwards to</FONT> <FONT SIZE=2 FACE="Courier New">your SIP registrar proxy, Registrar does a lookup on the SIP address and</FONT> <FONT SIZE=2 FACE="Courier New">finds that the user is register'd to</FONT><FONT SIZE=2 FACE="Courier New"> an analogue phone.</FONT> <FONT SIZE=2 FACE="Courier New">If the SIP registrar redirected using a 3xx response the * will play </FONT></SPAN></P>
<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New">along happily, but if the proxy wishes to stay in the loop (maybe you</FONT> <FONT SIZE=2 FACE="Courier New">have a billing application running on it) it would add a Record-Route</FONT> <FONT SIZE=2 FACE="Courier New">header to the SIP reque</FONT><FONT SIZE=2 FACE="Courier New">st , to say it wishes to receive all subsequent</FONT> <FONT SIZE=2 FACE="Courier New">messages for this call, and then proxy back to the *. The * will ignore</FONT> <FONT SIZE=2 FACE="Courier New">this INVITE totally. </FONT></SPAN></P>
<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New">If the user had been registered to a proper SIP end point then the loop </FONT></SPAN></P>
<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New">back wouldn't have happened and this wo</FONT><FONT SIZE=2 FACE="Courier New">rks a treat. </FONT></SPAN></P>
<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New">I'd like to know if there is any solution</FONT><FONT SIZE=2 FACE="Courier New"> to this problem.</FONT></SPAN></P>
<P ALIGN=LEFT><SPAN LANG="en-us"><FONT SIZE=2 FACE="Courier New">Thanks,</FONT></SPAN></P>
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