3Com NBX 100 Administrator's Manual - page 103
Managing Existing Virtual Tie Lines
103
Enabling Audio
Compression for VTL
Calls
You can set audio compression for VTL calls. The default condition is no
audio compression because compression can compromise audio quality.
For more information on how compression affects bandwidth, see
“Audio Settings”
on
page 257
.
During VTL call setup, the VTL software at each end of the call negotiates
a compression level that is supported by both systems. For example,
System A is configured for G729, high compression, and System B is
configured for G711, no compression. A VTL call between System A and
System B will use G711, no compression. It does not matter which system
initiates the call.
To enable VTL audio compression:
1 In the NBX NetSet - Main Menu window, click System Configuration.
2 On the System Settings tab click Audio Settings.
3 Click the Audio Compression on VTL Calls check box and then click OK.
Enabling Silence
Suppression on VTL
Calls
You can enable silence suppression for VTL calls. The default condition is
disabled because silence suppression can compromise audio quality. For
more information on how compression affects bandwidth, see
“Audio
Settings”
on
page 257
.
When you enable VTL silence suppression, the VTL software attempts to
use silence suppression on all VTL calls. If the other NBX system is not
configured to support silence suppression, the local VTL software
attempts to find a compatible communications mode.
Do not enable silence suppression unless you have network congestion
problems you cannot solve otherwise. Enabling silence suppression can
reduce network traffic, but the result is a compromise to audio quality.
Rerouted VTL calls
The number of calls that did not reach their destination
when attempted over VTL channels, and were rerouted using
another device.
Last reset command
The date and time of the most recent Reset for this VTL.
Last system reboot
The date and time of the most recent reboot of the NBX
system.
Table 21 Virtual Tie Line Statistics Fields (continued)
Field
Description