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<P> </P>
<P>Thanks for your reply :). </P>
<P> </P>
<P>My asterisk box and sip phone are not behind a nat, the sip phone and asterisk box are connected by LAN, so the delay is not caused by network congestion, and furthermore, there is no delay from sip to pstn.</P>
<P> </P>
<P>[sip phone]------LAN------[Asterisk with X100P]------[PSTN]</P>
<P>sip to pstn (no delay)</P>
<P>pstn to sip (half or one second delay)</P>
<P> </P>
<P>could you tell me <SPAN class=RVTS12>Mr. </SPAN><SPAN class=RVTS9>Andrew Kohsmith's</SPAN><SPAN class=RVTS11> email? I want to add him to my contact list.</SPAN></P>
<P> </P>
<P>Thanks.</P>
<P> </P>
<P> --- </P>
<P> Best regards,</P>
<P> Qiao Yuansong</P>
<P> mailto: qys@iscas.ac.cn</P>
<P> </P>
<P> Thursday, April 14, 2005, 9:08:19 PM, you wrote:</P>
<P> </P>
<P> </P>
<P> <SPAN class=RVTS6>> --- Qiao Yuansong </SPAN><SPAN class=RVTS7> wrote:</SPAN></P>
<P> </P>
<P> <SPAN class=RVTS6>>> At the beginning of a call, the latency is not very</SPAN></P>
<P> <SPAN class=RVTS6>>> long, but it becomes more and more obvious along</SPAN></P>
<P> <SPAN class=RVTS6>>> with time. If the call keep 10 minutes, the delay</SPAN></P>
<P> <SPAN class=RVTS6>>> will be about half or one second.</SPAN></P>
<P> <SPAN class=RVTS6>>> </SPAN></P>
<P> <SPAN class=RVTS6>>> Anyone knows the reason, and any suggestion?</SPAN></P>
<P> </P>
<P> <SPAN class=RVTS6>> Are you running your asterisk from behind a nat? My</SPAN></P>
<P> <SPAN class=RVTS6>> asterisk is behind a nat and I have the same problem</SPAN></P>
<P> <SPAN class=RVTS6>> with iax. Two other guys includong Mr. Andrew Kohsmith</SPAN></P>
<P> <SPAN class=RVTS6>> has the same issue and he is working on this problem.</SPAN></P>
<P> <SPAN class=RVTS6>> Today, he sent me an ip address to dial where he had</SPAN></P>
<P> <SPAN class=RVTS6>> echo test. The RTT (ping round trip time) from iax was</SPAN></P>
<P> <SPAN class=RVTS6>> low and the same almost all the time and the jitter</SPAN></P>
<P> <SPAN class=RVTS6>> was down to zero to this his server.</SPAN></P>
<P> </P>
<P> <SPAN class=RVTS6>> the high jitter (variation in packet delay) causing a</SPAN></P>
<P> <SPAN class=RVTS6>> compounding problem that eventually cause the</SPAN></P>
<P> <SPAN class=RVTS6>> communication break down.The question becomes what is</SPAN></P>
<P> <SPAN class=RVTS6>> the source of the jitter: network layer, low internet</SPAN></P>
<P> <SPAN class=RVTS6>> bandwidth or some iax.conf or sip.conf configuration</SPAN></P>
<P> </P>
<P> </P>
<P> </P>
<P> </P>
<P> </P>
<P> <SPAN class=RVTS6>> __________________________________ </SPAN></P>
<P> <SPAN class=RVTS6>> Do you Yahoo!? </SPAN></P>
<P> <SPAN class=RVTS6>> Make Yahoo! your home page </SPAN></P>
<P> <SPAN class=RVTS6>> http://www.yahoo.com/r/hs</SPAN></P>
<P> </P>
<P> </P>
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