Quality Of Service <Qos - Polycom SIP 2.2.0 Administrator's Manual

Attribute
voice.vadEnable
voice.vadThresh
voice.vad.signalAnnex
B
Quality of Service <QOS/>
Voice Activity Detection <vad/>
These settings control the performance of the voice activity detection (silence
suppression) feature.
Permitted
Values Default
0, 1 0
integer from 0 15
to 30
0, 1 Null
These settings control the Quality of Service (QOS) options.
This attribute includes:
• Ethernet IEEE 802.1p/Q <ethernet/>
• IP TOS <IP/>
Ethernet IEEE 802.1p/Q <ethernet/>
The following settings control the 802.1p/Q user_priority field:
• RTP <RTP/>
• Call Control <callControl/>
• Other <other/>
Interpretation
If set to 1, enable VAD.
The threshold for determining what is active voice and
what is background noise in dB. This does not apply to
G.729AB codec operation which has its own built-in VAD
function.
If set to 1 and voice.vadEnable is set to 1, Annex B is
used. A new line can be added to SDP depending on the
setting of this parameter and the voice.vadEnable
parameter.
• If voice.vadEnable is set to 1, add attribute line
a=fmtp:18 annexb="yes" below a=rtpmap... attribute
line (where '18' could be replaced by another
payload).
• If voice.vadEnable is set to 0, add attribute line
a=fmtp:18 annexb="no" below a=rtpmap... attribute
line (where '18' could be replaced by another
payload).
If set to 0 or Null, there is no change to SDP.
Configuration Files
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