[asterisk-users] Question about echo cancelation

[Olivier]

2008/10/11 Eric ManxPower Wieling <eric at fnords.org>

>
>
> Olivier wrote:
> > 2008/10/10 Eric ManxPower Wieling <eric at fnords.org>
> >
> >> All calls with a 2-wire analog piece have echo.  You cannot perceive the
> >> echo because it happens so fast on non-VoIP connections.  On VoIP calls
> >> you have significant extra latency while causes you you to perceive the
> >> echo.
> >
> > Do you mean "generated locally" or "generated distantly" ?
> >
> > I understand that VoIP extra latency sometrimes renders perceivable what
> was
> > unperceivable before.
> > What suprises me is to hear that media getways "filter one-way only" : as
> > 2-wires analog devices produce echo, and every phone has 2-wires analog
> > audio, in every call you've got at least 2 sources of echo : one in each
> > endpoint.
>
> Where did you hear that media gateways "filter one-way only"?