[Asterisk-Users] E1 Echo

[Florian Overkamp]

Andrew Kohlsmith wrote:
> On Friday 16 December 2005 08:12, Florian Overkamp wrote:
> 
>>Although it's a bit unclear how things evolved exactly (since no-one
>>ever tells us), a number of interconnection points throughout the
>>country were consolidated, significantly increasing the chance that
>>delay exceeded 128 taps.
> 
> 
> I need to do some investigation of bringing the tap count WELL above that... 
> I'd like to see what kind of performance we can get with 128 MILLISECOND 
> tail...  128 taps is only 16ms...  and 16ms of echo cancel is damn near 
> useless, as it's fast enough that you'd likely not even hear the echo as 
> anything more than a sidetone anyway.
> 
> I imagine it's deathly hard on the CPU though.  :-)

Actually, the problem is different. If you receive an echo on the PSTN 
gateway that has a 16ms echo, the problem would not be noticeable there, 
but if you then add a VoIP connection the delay added would make the 
echo audible.

Florian