[Asterisk-Users] echo cancelation

[Linus Surguy]

HI all,

Having a mental block today - can someone confirm which direction the echo
cancelation applies to for the Zap PRI channels?

ie. is it removing traces of the transmitted data to the PSTN from the
received data,

*or* is it removing traces of the data transmitted to Asterisk from the data
received back from Asterisk?

Got a configuration that is based on a call made from the PSTN to a SIP
user:

PSTN -> Telco Switch -> PRI -> Asterisk -> SIP -> X-Lite

PSTN caller hears no echo
X-Lite user hears significant (1 second or so) echo

If we setup a call so that the 'telco switch' runs an IVR process instead of
linking to the PSTN, keeping the call entirely in the digital domain so no
signal reflection the X-Lite user does not hear echo.

Echocancel=yes etc. is enabled in the zapata.conf

Which party is at fault?

Linus