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<DIV><!--StartFragment --><FONT face=Arial><FONT size=2><SPAN
class=383081720-23032005>></SPAN>Peter Svensson wrote:<BR><SPAN
class=383081720-23032005></SPAN>><BR><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><FONT face=Arial><FONT
size=2><I>On Tue, 22 Mar 2005, McQuiggan, Mark xt46480 wrote:<BR></I><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><I><BR></I><FONT
face=Arial><FONT size=2><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><FONT face=Arial><FONT
size=2><I> <BR></I><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><I><BR></I><FONT
face=Arial><FONT size=2><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I>I am using a SIP softphone (X-lite, SIPPS or Firefly) connected to
an<BR></I><SPAN class=383081720-23032005>></SPAN>>></FONT></FONT><FONT
face=Arial><FONT size=2><I>Asterisk v 1.0.3 PBX. The PBX is also connected
via a ISDN-PRI crossover<BR></I><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><I><FONT face=Arial
size=2>cable to a Avaya Definity Generic 3 PBX via a TE405P card. All outside
of</FONT></DIV>
<DIV></I><FONT face=Arial><FONT size=2><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I>the office calls go through the Definity. Here's the
issue:<BR></I><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I> <BR></I><SPAN class=383081720-23032005>></SPAN>>><EM>Calls
to internal SIP extensions, Definity extensions, other offices
within</EM><BR><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I>our private network (through the Definity), and cell phones are
great. When<BR></I><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I>I call outside of the office to POTS lines (like my home), there is a
most<BR></I><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I>noticeable echo of my voice. The party on the line hears no
echo. Any<BR></I><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I>efforts on the configuring the SIP softphones, and within zapata.conf,
have<BR></I><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I>been for naught.<BR></I><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I> <BR></I><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I>Is this problem common for ISDN-PRI connections?<BR></I><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><FONT face=Arial><FONT
size=2><I> <BR></I><SPAN
class=383081720-23032005>></SPAN>>></FONT></FONT><I><BR></I><FONT
face=Arial><FONT size=2><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><I><BR></I><FONT
face=Arial><FONT size=2><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><FONT face=Arial><FONT
size=2><I>It is a problem you will see when calling an analogue subscriber over
a <BR></I><SPAN class=383081720-23032005>></SPAN>></FONT></FONT><FONT
face=Arial><FONT size=2><I>link with a long latency (such as VoIP). The echo
will most probably be <BR></I><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><FONT face=Arial><FONT
size=2><I>generated by a 2- to 4-wire hybrid at the far end. In a pure
amalogue/tdm <BR></I><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><FONT face=Arial><FONT
size=2><I>path you would perceive the reflected energy as a plesent sidetone. As
<BR></I><SPAN class=383081720-23032005>></SPAN>></FONT></FONT><FONT
face=Arial><FONT size=2><I>soon as the latency increases to 50-100ms the
refelcted energy will be <BR></I><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><FONT face=Arial><FONT
size=2><I>perceived as an echo instead.<BR></I><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><I><BR></I><FONT
face=Arial><FONT size=2><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><FONT face=Arial><FONT
size=2><I>The options available to you are to live with the echo of your own
voice <BR></I><SPAN class=383081720-23032005>></SPAN>></FONT></FONT><FONT
face=Arial><FONT size=2><I>or to insert an echo canceller at the pstn interface.
Asterisk includes an <BR></I><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><FONT face=Arial><FONT
size=2><I>echo canceller that may or may not be good enough. It seems to like
some <BR></I><SPAN class=383081720-23032005>></SPAN>></FONT></FONT><FONT
face=Arial><FONT size=2><I>pstn interfaces and not others. If the Asterisk echo
canceller is not <BR></I><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><FONT face=Arial><FONT
size=2><I>enough you may consider an expensive inline echo canceller.
<BR></I><SPAN class=383081720-23032005>></SPAN>></FONT></FONT><FONT
face=Arial><FONT size=2><I> <BR></I><SPAN
class=383081720-23032005>></SPAN>></FONT></FONT><I><BR></I><FONT
face=Arial><FONT size=2><SPAN class=383081720-23032005>></SPAN><BR><SPAN
class=383081720-23032005>></SPAN>The definity has echo cancellation. Try
turning that on.<BR><SPAN class=383081720-23032005>></SPAN><BR><SPAN
class=383081720-23032005>></SPAN>-SteveK</FONT></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial size=2>Thanks for both of
your replies. </FONT></SPAN></DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial size=2>My Definity
connection is on a TN464C (the TN464G has echo cancellation) and I was hoping
to try a software solution first before investing in the hardware (we would
also have to upgrade our Definity software, so the total cost is quite
high).</FONT></SPAN></DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial size=2>I have noticed
that any of the zapata.conf echo cancel parameters seem to have no effect on an
ISDN-PRI line, using pri_net signalling (I used the voip-info.org wiki for the
configuration). If this is true, and I am not making some dumb mistake, is
there another signalling mode that I can use on a Definity that will take
advantage of echo-cancel?</FONT></SPAN></DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial size=2>Barring that, I am
using a Plantronics DSP-100 headset with X-lite under Windows. Can I set
up echo-cancelling there?</FONT></SPAN></DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial
size=2>Thanks,</FONT></SPAN></DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial
size=2>Mark.</FONT></SPAN></DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=383081720-23032005><FONT face=Arial size=2>P.S. Is there
a website where I can post replies to this mailing list? Cutting and
pasting into Outlook is just darn goofy.
M.</FONT></SPAN></DIV><div><p><font size="2"><FONT face=Arial color=#0000ff size=2><BR><BR>
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