3Com MSR 50 Series, Configuration Manual

Page: 2389 / 2443

Configuring VoFR Voice Bandwidth 2389
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In the dynamic mode, the DTMF transmission mode is determined by the
configuration of the VoFR entity on the originating side.
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In the FRF.11 trunk mode, the DTMF transmission mode is determined by the
configurations of the VoFR entities on the originating and terminating sides.
Enabling VAD Follow these steps to enable the voice activity detection (VAD):
Configuring VoFR
Voice Bandwidth
You can reserve the maximum amount of voice bandwidth to control the
maximum number of calls. If the required bandwidth is not greater than the
remaining bandwidth, a new call is allowed. Otherwise, the new call is rejected.
For example, the reserved bandwidth is 64 kbps and each call requires a
bandwidth of 10 kbps, then only six calls can be set up concurrently and a seventh
call will be rejected. In the case of concurrent transmission of voice and data over
a channel, the voice bandwidth is processed in the following two ways:
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A bandwidth is reserved for voice to prevent the case that the voice quality is
degraded because of the consumption of the whole bandwidth by burst data.
Once a call is set up successfully, the bandwidth will be exclusively occupied by
voice until the call is completed.
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Voice takes precedence over data. The actual bandwidth in a call changes
dynamically. When no data is transmitted, the silence packets sent occupies
only a very small portion of bandwidth. This method can avoid the bandwidth
waste caused by bandwidth reservation for voice.
To do... Use the command... Remarks
Enter system view system-view -
Enter voice view voice-setup -
Enter voice dial program view dial-program -
Create a VoFR entity and
enter VoFR entity view entity entity-number vofr -
Configure a match template
for the VoFR entity match-template
match-string
Required
By default, no match template
is configured for the VoFR
entity.
Configure the out-of-band
DTMF transmission mode outband vofr Required
By default, the inband DTMF
transmission is configured.
To do... Use the command... Remarks
Enter system view system-view -
Enter voice view voice-setup -
Enter voice dial program view dial-program -
Create a VoFR entity and
enter VoFR entity view entity entity-number vofr -
Enable VAD vad-on Required
Disabled by default.
Note that the G.711 codec
does not support VAD.