Configuring Voice over IP
Configuring Basic VoIP
101
Cisco VGD 1T3 Voice Gateway Software Configuration Guide
Configuring Echo Cancellation on the Voice Feature Card
The echo-cancel enable command enables cancellation of voice that is sent out the interface and
received back on the same interface; sound that is received back in this manner is perceived by the
listener as an echo. Disabling echo cancellation might cause the remote side of a connection to hear an
echo. Because echo cancellation is an invasive process that can minimally degrade voice quality, this
command should be disabled if it is not needed.
For the voice feature card, software echo cancellation is the default configuration—G.168-compliant
echo cancellation is enabled by default with a coverage of 64 milliseconds. Hardware echo cancellation
is not available.
3
—
5...
voip
—
172.19.1.1
6.711
best effort
4
6000
6000
pots
1/0:3
—
—
—
Table 7
Dial-Peer Configuration Table
Dial-Peer Tag
Extension
Destination
Pattern
Type
Voice Port Session Target
Codec
QoS
Command or Action
Purpose
Step 1
enable
Example:
Router> enable
Enables privileged EXEC mode.
•
Enter your password if prompted.
Step 2
configure terminal
Example:
Router# configure terminal
Enters global configuration mode.
Step 3
voice-port
slot
/
port
:
channel
Example:
Router(config)# voice-port 2/0:1
Enters voice-port configuration mode and
identifies a slot, port, and channel for
configuration parameters.
Step 4
echo-cancel enable
Example:
Router(config-voiceport)# echo-cancel
enable
Enables the cancellation of voice that is sent out
the interface and received back on the same
interface.
Step 5
echo-cancel coverage
{
24
|
32
|
48
|
64
|
80
|
96
|
112
|
128
}
Example:
Router (config-voiceport)# echo-cancel
coverage 96
Adjusts the echo canceller by the specified number
of milliseconds.
•
The default is 128.
Step 6
exit
Example:
Router(config-voiceport)# exit
Exits voice-port configuration mode and returns to
global configuration mode.
