3Com NBX 100 Administrator's Manual - page 41
Audio Settings
41
Silence Suppression
Overview
Silence suppression is a method of reducing the number of packets
transmitted during a conversation. Silence suppression can help you avoid
dropped packets on a congested network. During a conversation there
are periods of silence. A packet of silence takes up as much bandwidth as
a packet with audio data. If you enable Silence Suppression, the
telephone sends a silence indicator when it senses the start of a silent
period and it suppresses all subsequent voiceless frames. When another
NBX device receives this indicator, it generates and inserts white noise
until it receives the next frame that contains audio data. If you enable
Silence Suppression, a careful listener might notice a difference in audio
quality. The background white noise generated by the receiving
telephone is subtly different from the silence in an audio stream.
Silence suppression results in compromises to audio quality. Do not
enable suppression unless you are trying to solve network bandwidth
congestion issues that you cannot solve through other means, such as
increasing network capacity.
To enable Silence Suppression, click System-Wide Settings > Audio
Settings.
3Com 3108 Wireless Telephone
3C10408A
Yes
Yes
Yes
No
No
No
Analog Terminal Adapter
3C10120
3C10120B
No
Yes
Yes
N / A
N / A
N / A
3C10400
Yes
Yes
Yes
N / A
N / A
N / A
Analog Terminal Card
3C10117
3C10117B-INT
No
Yes
Yes
N / A
N / A
N / A
3C10117C
Yes
Yes
Yes
N / A
N / A
N / A
Analog Line Card
3C10114
3C10114-ANZ
No
Yes
Yes
N / A
N / A
N / A
3C10114C
Yes
Yes
Yes
N / A
N / A
N / A
Digital Line Card
3C10116,
3C10116B
3C10116C
3C10164-ST (BRI)
3C10164C-ST (BRI)
3C10165
3C10165C
No
Yes
Yes
N / A
N / A
N / A
3C10116D
3C10165D
Yes
Yes
Yes
N / A
N / A
N / A
Table 11 Audio Encoding Supported by NBX Devices (continued)
Device
Part Number
G.729
ADPCM G.711
G.722
G.722.2 G.722.2LB