Huawei AR1200 Series Configuration Manual - Voice page 42

Huawei AR1200 Series Enterprise Routers
Configuration Guide - Voice
Enabling Echo Cancellation on a DSP Channel
This section describes how to enable echo cancellation on a DSP channel.
Context
A user may hear the user's echo in the phone receiver in a conversation. If a proper delay in the
transmitted or received signal is set, the echo can be removed. If the delay exceeds 25 ms, the
voice quality deteriorates and the conversation ends. You can enable echo cancellation on a DSP
channel to remove echoes.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
voice
The voice view is displayed.
Step 3 Run:
dsp
The DSP view is displayed.
Step 4 Run:
echo enable
Echo cancellation is enabled on the DSP channel.
----End
Enabling the PLC Function on a DSP Channel
This section describes how to enable the packet loss concealment (PLC) function on a DSP
channel.
Context
PLC is a technique that masks the effects of packet loss in VoIP communications. PLC is
effective only when the packet loss ratio is low. During communication, the average packet loss
ratio may be low, but a high burst packet loss ratio results in severe voice quality deterioration.
PLC can insert a static frame in the place where a packet is lost, regenerate a packet received
prior to the lost one, or generate an analog voice packet. If packets are lost during communication
and PLC is not used, the voice communication is interrupted. You can use a proper PLC
algorithm to minimize effects of packet losses.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Issue 03 (2011-09-30) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
1 SIPAG Configuration
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