Comfort Noise Generation - Yealink SIP-T4X Administration Manual

Comfort Noise Generation (CNG) is used to generate background noise for voice
communications during periods of silence in a conversation. It is a part of the silence
suppression or VAD handling for VoIP technology. CNG, in conjunction with VAD
algorithms, quickly responds when periods of silence occur and inserts artificial noise
until voice activity resumes. The insertion of artificial noise gives the illusion of a constant
transmission stream, so that background sound is consistent throughout the call and the
listener does not think the line has released. The purpose of VAD and CNG is to maintain
an acceptable perceived QoS while simultaneously keeping transmission costs and
bandwidth usage as low as possible.
Procedure
CNG can be configured using the configuration files or locally.
Configuration File
Local
To configure CNG via web user interface:
1. Click on Settings->Voice.
2. Select the desired value from the pull-down list of CNG.
3. Click Confirm to accept the change.
<y0000000000xx>.cfg
Web User Interface
Configuring Audio Features
Configure CNG.
For more information, refer to

Comfort Noise Generation

page 364.
Configure CNG.
Navigate to:
http://<phoneIPAddress>/servl
et?p=settings-voice&q=load
on
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