Avaya G430, Manual

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is in the echo path of a longer tail canceller, audible echo can result when echo exists partly
in one canceler's window and partly in the other.
For cases where there is no echo to cancel, it is usually best to disable any echo canceller in
the path. Echo cancellers are not totally transparent and sometimes introduce undesirable
artifacts.
However, the best echo cancellation policy varies depending on each specific call
configuration. The Branch Gateway has an internal table for determining which VoIP engine
and analog card echo cancellers to enable on a case-by-case basis. This table is consulted
when the default auto mode is specified in the echo cancellation CLI commands. The CLI
commands also offer the option of overriding the default automatic mode, but those alternative
modes are intended for debugging and diagnostics purposes only.
Note:
DS1 echo cancellation can only be administered via the Communication Manager SAT, and
these settings are always honored by the Branch Gateway. Therefore, the Branch Gateway
CLI controls only the operation of the VoIP engine and analog trunk/line echo cancellers in
relation to the DS1 echo canceller and between themselves.
Related topics:
Summary of echo cancellation commands on page 411
Summary of echo cancellation commands
For more information about these commands, see the Avaya Branch Gateways G250 and
G350 CLI Reference .
For more information about these commands, see the Avaya Branch Gateway G430 CLI
Reference .
Command Description
set echo-cancellation
analog Control echo cancellation on analog lines and
trunks.
The recommended setting for all analog trunks and
lines is the default auto mode. In this mode, the
Media Gateway controller consults internal rules to
determine when to employ the analog echo
canceller for each call.
set echo-cancellation
config analog Configure echo cancellation on analog lines and
trunks
The recommended setting for all analog trunks and
lines is the default configuration. The rest of the
configuration options are intended for debugging or
diagnosing issues in the field.
Monitoring applications
Administering Avaya G430 Branch Gateway October 2013 411