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<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT face=Arial
color=#0000ff size=2>Dear Scott,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT face=Arial
color=#0000ff size=2>Many parameters are causing echo. My suggestion is,
please find another IP Phone (or ATA ) and try to connect &
test on different points like (1,2,3,4) and </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT face=Arial
color=#0000ff size=2>get some samples. Making these test you may narrow
your problem area.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT face=Arial
color=#0000ff size=2>Are you using activity detection (VAD), jitter buffer, and
echo cancellation on your IP Phone or VGW side ? which codec is
you are using ? </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT face=Arial
color=#0000ff size=2>Please try to read these documents.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT color=#800080
size=3><STRONG>Echo Analysis for Voice over IP</STRONG></FONT></DIV></SPAN>
<DIV dir=ltr align=left><SPAN class=810343601-03112005><FONT face=Arial
color=#0000ff size=2><A
href="http://www.cisco.com/en/US/tech/tk652/tk701/technologies_white_paper09186a00800d6b68.shtml">http://www.cisco.com/en/US/tech/tk652/tk701/technologies_white_paper09186a00800d6b68.shtml</A></FONT></SPAN></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><!--StartFragment --><STRONG><FONT color=#800080 size=3>Understanding Delay
in Packet Voice Networks</FONT><FONT face=Arial
color=#0000ff></FONT></STRONG></DIV>
<DIV><FONT face=Arial color=#0000ff size=2><A
href="http://www.cisco.com/en/US/tech/tk652/tk698/technologies_white_paper09186a00800a8993.shtml">http://www.cisco.com/en/US/tech/tk652/tk698/technologies_white_paper09186a00800a8993.shtml</A></FONT><BR></DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#ff0000><STRONG>Also
you can try to investigate your echo using some tools or Cisco
commands</STRONG></FONT></SPAN></DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#0000ff size=2><A
href="http://www.fastmirrors.org/smokeping/probes/ciscorttmonechoicmp.en.html">http://www.fastmirrors.org/smokeping/probes/ciscorttmonechoicmp.en.html</A></FONT></SPAN></DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=810343601-03112005><SPAN class=810343601-03112005><FONT
color=#ff0000 size=4><FONT color=#008080>Measuring Delay, Jitter, and Packet
Loss with Cisco IOS SAA and RTTMON</FONT><BR></FONT><FONT face=Arial
color=#0000ff size=2><A
href="http://www.cisco.com/en/US/tech/tk869/tk769/technologies_white_paper09186a00801b1a1e.shtml">http://www.cisco.com/en/US/tech/tk869/tk769/technologies_white_paper09186a00801b1a1e.shtml</A></FONT></SPAN></SPAN></DIV>
<DIV><SPAN class=810343601-03112005><SPAN class=810343601-03112005><FONT
face=Arial color=#0000ff size=2></FONT></SPAN></SPAN> </DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#0000ff size=2><A
href="http://www.cisco.com/en/US/tech/tk648/tk362/technologies_white_paper0900aecd8022c2cc.shtml">http://www.cisco.com/en/US/tech/tk648/tk362/technologies_white_paper0900aecd8022c2cc.shtml</A></FONT></SPAN></DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#0000ff size=2><A
href="http://www.cisco.com/en/US/tech/tk648/tk362/technologies_q_and_a_item09186a00802146c3.shtml">http://www.cisco.com/en/US/tech/tk648/tk362/technologies_q_and_a_item09186a00802146c3.shtml</A></FONT></SPAN></DIV>
<DIV><SPAN class=810343601-03112005><!--StartFragment --> </SPAN></DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#0000ff
size=2>Regards,</FONT></SPAN></DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#0000ff size=2>Cumhur
</FONT></SPAN></DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=810343601-03112005><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> cisco-voip-bounces@puck.nether.net
[mailto:cisco-voip-bounces@puck.nether.net] <B>On Behalf Of </B>Voll,
Scott<BR><B>Sent:</B> Wednesday, November 02, 2005 01:21<BR><B>To:</B> ci
>> "cisco-voip@puck-nether.net"<BR><B>Subject:</B> [cisco-voip]
Echo<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV class=Section1>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Can someone tell me where to start
looking? I have reports of echo / voice cutting out in the following
topology:<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT color=#0000ff><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p><SPAN
class=810343601-03112005>Phone One</SPAN></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">IP Phone – Switch – Router – T1 FR –
ATM DS3 – Router – CM – VGW – PRI – PSTN<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> <SPAN
class=810343601-03112005><FONT
color=#0000ff> <FONT
color=#ff0000>
<STRONG>1</STRONG></FONT>
<FONT
color=#ff0000><STRONG>2</STRONG> </FONT> <STRONG>
<FONT
color=#ff0000>3</FONT></STRONG> <FONT
color=#ff0000><STRONG> 4</STRONG></FONT>
</FONT></SPAN></o:p></SPAN></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I just changed the QoS to include
CS3 in my control QoS as Cisco changed that and I don’t know if that will fix
it.<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Thanks<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Scott<o:p></o:p></SPAN></FONT></P></DIV></BODY></HTML>