Command Reference Guide

3Com Router 5000 Family and Router 6000 Family echo-canceller ● 147
Command Reference
[Router-voice-line1/0/0] echo-canceller enable
[Router-voice-line1/0/0] echo-canceller tail-length 24
View This command can be used in the following views:
■ Voice Subscriber-Line view
Description During a call, the voice of a subscriber may be echoed back to the handset. This is
because analog voice signals are leaked into the reception path of the subscriber. You
can use the echo-cancellation function provided by the voice gateway to solve this
problem to a certain extent.
If a too large time value is set, the converge time of the echo canceling on the
network will become longer, so when the connection has just been established, the
user may hear the echo; and if the time value is set as too small, the user may also
hear part of the echo, because the relatively longer echo has not been completely
cancelled.
There are no echo and echo-cancel on the IP side.
Signal leakage occurs only on the analog circuit part of the voice call path. Digital
networks do not suffer from this problem.
■ The echo-canceller enable command must be used in pair with the
echo-canceller tail-length command.
■ This command applies to FXO and FXS interfaces.
Related Command subscriber-line