User manual

Chapter 3: Configuration
any channel. So, it is very important that you specify one in the
system.conf file if you do not have hardware echo cancellers and need
echo cancellation. The format is:
echocanceller = <echocanceller name>,<channel(s)>
A list of valid echo cancellers are specified in the sample system.conf
file.
The following is a typical setup for a T1 PRI in the US using software-
based echo cancellation:
echocanceller = mg2,1-23
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