SMC Networks 7908VOWBRA - annexe 7 Manual page 132

C
ONFIGURING THE
Port Advanced Setting
There are 10 advanced functions that can be configured in this screen for
phone1/phone2.
• Volume Gain Control: Two modes are available. The fixed gain
control means the device is supported to supply a constant level of
amplification.
The adaptive mode means a specified power level is produced at the
output during periods of active speech.
• Jitter Buffer Mode: Three jitter modes are available. The fixed
mode, which is the default mode, is a simple first in first out mode, with
a fixed jitter buffer delay.
The adaptive mode optimizes the size of the jitter buffer delay in
response to network conditions.
The sequential mode is also a fixed jitter buffer delay mode, but in this
mode the jitter buffer function looks at the packet number for dropped
or out of sequence packet problems.
• Jitter Buffer Delay: This parameter represents the delay in
milliseconds that the jitter buffer waits before it transmits the data
samples that are collected from the host processor to the CODEC.
• Echo Canceller Delay: This is the function that filters out echoes
occurred during periods of active speech.
• VAD (Voice Activity Detection): If this box is checked, only a
certain level of voice volume will be send out as voice packets. This
function is designed to save the bandwidth.
• CNG (Comfort Noise Generation): Check this box to enable the
Comfort Noise Generation function. When no one is talking on a call
this feature will generate comfort noise in the background so you know
the call is active.
4-90
V ADSL R
OICE OUTER