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</o:shapelayout></xml><![endif]--></head><body lang=FR-CH link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=DE-CH>Hello,<o:p></o:p></span></p><p class=MsoNormal><span lang=DE-CH><o:p> </o:p></span></p><p class=MsoNormal>I am experiencing some disconnections with my VOIP phones.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Let me explain:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=DE-CH>My server is an Asterisk + Kamailio in a datacenter with a fixed IP, and a bridge firewall in front of it, so no NAT here.<o:p></o:p></span></p><p class=MsoNormal><span lang=DE-CH><o:p> </o:p></span></p><p class=MsoNormal>My client (several offices) have usually no problem when they have a fixed IP, but encounter fatal disconnection when they have a dynamic IP. I had the case with Siemens, SNOM and Aastra phones, without any difference. <span lang=DE-CH>They are of course natted behind an ADSL router. I also have clients doing load-balance between two ADSL lines, which is also problematic.<o:p></o:p></span></p><p class=MsoNormal><span lang=DE-CH><o:p> </o:p></span></p><p class=MsoNormal>The only way for me to recover is to change the private IP of the VOIP phones. <span lang=DE-CH>Seems more like a TCP problem or a routing problem, but I am no network guru.<o:p></o:p></span></p><p class=MsoNormal><span lang=DE-CH><o:p> </o:p></span></p><p class=MsoNormal><span lang=DE-CH>I have two ADSL lines to test it, and when I switch from one line to another, every phone becomes „Not registered“. Even falling back tot he first line does not help recovering. </span>I did not try to wait for longer than 24 hours to recover.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>So my question is, more generally: is it possible to allow the clients (VOIP phones) to re-connect with a new IP address without having closed correctly the first connection (SIP session, I presume)? <span lang=DE-CH>It seems not by default, but I played with the timeouts server-side and phone-side, without luck.<o:p></o:p></span></p><p class=MsoNormal><span lang=DE-CH><o:p> </o:p></span></p><p class=MsoNormal>I saw many posts with PBX having problems when behind a dynamic IP, but nothing about the clients having dynamic addresses or load-balancing. Normally, having a dynamic IP does not mean that your IP will change « on-the-fly », but each time you shut down and reboot later your ADSL router, but we came to the conclusion that every client NOT having a fixed IP was experiencing fatal disconnects. <span lang=DE-CH>So I managed to test and validate this behavior with our two ADSL lines.<o:p></o:p></span></p><p class=MsoNormal><span lang=DE-CH><o:p> </o:p></span></p><p class=MsoNormal>Hope someone can help me.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Greetings<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Simon<o:p></o:p></p></div></body></html>