3Com VCX V7122, User Manual

Page: 235 / 488

V7122 Gateway User Guide
235
ini File Field Name
Web Parameter Name
Valid Range and Description
EnableSilenceCompression
[Silence Suppression]
The parameter
SCE is used to
maintain backward compatibility.
0 = Silence Suppression disabled (default).
1 = Silence Suppression enabled.
2 [Enable without adaptation] = A single silence packet is sent during
silence period (applicable only to G.729).
Silence Suppression is a method conserving bandwidth on VoIP calls
by not sending packets when silence is detected.
If the selected coder is G.729, the following rules determine
the value of the ‘annexb’ parameter of the fmtp attribute in
the SDP.
EnableSilenceCompression = 0
Æ
‘annexb=no’.
EnableSilenceCompression = 1 Æ ‘annexb=yes’.
EnableEchoCanceller
[Echo Canceler]
The parameter
ECE is used to
maintain backward compatibility.
0 = Echo Canceler disabled.
1 = Echo Canceler Enabled (default).
Refer also to the parameters ‘MaxEchoCancellerLength’
(described in
Table 36 ).
MaxEchoCancellerLength
[Max Echo Canceller Length]
Note:
It is not necessary to
configure the parameter
EchoCancellerLength as it
automatically acquires its value
from the parameter
MaxEchoCancellerLength.
Maximum Echo Canceler Length in msec:
0 = based on various internal gateway settings -- 64 msec (default)
4 = 32 msec
11 = 64 msec
22 = 128 msec
When set to 128 msec, the number of available gateway
channels is reduced by a factor of 5/6.
For example:
Gateway with 8 E1 spans capacity is reduced to 6 spans
(180 channels), while gateway with 8 T1 spans capacity
remains the same (192 channels).
The gateway must be reset after the value of
‘MaxEchoCancellerLength’ is changed.
EchoCancellerAggressiveNLP Enables or disables the Aggressive NLP in the first 0.5 second of the
call.
0 = Disabled (default)
1 = Enabled
EnableNoiseReduction Enables / disables the DSP Noise Reduction mechanism.
0 = Disable (default).
1 = Enable.
When this parameter is enabled the channel capacity might
be reduced.
EnableStandardSIDPayloadTyp
e
[Enable RFC 3389 CN Payload
Type]
Determines whether Silence Indicator (SID) packets that are sent and
received are according to RFC 3389.
0 = G.711 SID packets are sent in a proprietary method (default).
1 = SID (comfort noise) packets are sent with the RTP SID payload type
according to RFC 3389. Applicable to G.711 and G.726 coders.