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<TITLE>Establish a session with a user behind 2 NATs</TITLE>
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<FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>Hello,<BR>
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I have this problem and it only appears when a remote user is behind two NATs and when I(behind one NAT) try to establish the session. The scenario is: I send a INVITE to the remote client through the server, I receive the 100 Trying for that INVITE, after that, the remote client sends a 200/OK message but apparently the server never replies to that OK or other subsequent 200/OKs. When I run a tcpdump on the server I see that the ACK for the OK is actually sent but at the wrong address. It’s sent to 192.168.X.X which is the internal address of the second router instead of sending to the public address of the first router. <BR>
Does anybody know why this is happening and how this could be fixed?<BR>
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I am using sipsimple on the client side and the OpenSIPS server<BR>
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Thank you,<BR>
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Mihai Richard</SPAN></FONT>
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