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section of an audio session. It can avoid unnecessary
coding or transmission of silence packets in VoIP
applications, saving on computation and network
bandwidth.
CNG (Comfort Noise Generation): Allow IP phone to
generate comfortable 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.
Jitter Buffer
Jitter buffer is a shared data area where voice packets can be
collected, stored, and sent to the voice processor in even
intervals. Jitter is a term indicating variations in packet arrival
time, which can occur because of network congestion, timing
drift or route changes. The jitter buffer, located at the
receiving end of the voice connection, intentionally delays
the arriving packets so that the end user experiences a clear
connection with very little sound distortion.
IP phones support two types of jitter buffers: fixed and
adaptive.
Fixed: Add the fixed delay to voice packets. You can configure
the delay time for the static jitter buffer on IP phones.
Adaptive: Capable of adapting the changes in the network's
delay. The range of the delay time for the dynamic jitter
buffer added to packets can be also configured on IP phones.
Mic Volume
To configure Microphone volume for headset, handset and
speaker mode.
5.10.Phone->Key/Display
Path: Web UI->Phone->Key/Display
