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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I have been in the process of trying to troubleshoot a phone
system that is doing IAX trunking to a provider. The average RTA is 75ms with
spikes from time to time and jitter from time to time as well. My question is
this; How much can one trust this types of samples when going over the
internet? I mean who knows who is doing what kind of ICMP rate limiting or
dropping ICMP all together? What is a good measurement or troubleshooting step
for intermittent bad quality when dealing with links that you have no control
over or is that even relevant? Here is our setup:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>All outbound calls are going out POTS unless that line is
congested. All inbound (even from the POTS as it is forwarded directly to an IP
DID) are over the IAX trunk. We are not seeing any issues on outbound calls. On
inbound, however, we are getting intermittent choppy voice, echo and cutting
out. This is heard by the person coming in, i.e when someone is calling they
hear these symptoms of the users on the asterisk server. From our side the
issue doesn’t seem to exist or it is so much less that it is really
irrelevant. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>As I have mentioned I have seen spikes of ping times and
times of jitter but this is recognized by tools utilizing ICMP so I don’t
know how much I can trust them. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thanks for the help!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Curt<o:p></o:p></span></font></p>
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