R2511-HP MSR Router Series Voice Configuration Guide(V5)
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NOTE:
• In the dynamic mode, the DTMF transmission mode is determined by the confi
g
uration of the VoFR entit
y
on the originating side.
• In the FRF.11 trunk mode, the DTMF transmission mode is determined by the confi
g
urations of the VoFR
entities on the originating and terminating sides.
Enabling VAD
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter voice view.
voice-setup N/A
3. Enter voice dial program
view.
dial-program N/A
4. Create a VoFR entity and
enter VoFR entity view.
entity entity-number vofr
N/A
5. Enable VAD.
vad-on
Disabled by default.
Note that the G.711 codec does
not support 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 ways:
• A bandwidth is reserved for voice to prevent degradation of voice quality due to 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.
• Voice takes precedence over data. The actual bandwidth in a call changes dynamically. When no
data is transmitted, the silence packets sent occupy only a very small portion of bandwidth. This
method avoids the bandwidth waste caused by bandwidth reservation for voice.
To configure VoFR voice bandwidth:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Create a frame relay class
and enter frame relay class
view.
fr class class-name N/A
3. Reserve a bandwidth for
voice.
voice bandwidth reserved-bps [ reserved ]
By default, no
bandwidth is reserved
for voice.
4. Exit frame relay class view.
quit N/A