Grandstream Networks GXW400x User Manual
Page 30
Grandstream Networks, Inc.
GXW-400x User Manual
Page 30 of 39
Firmware 1.0.0.39
Last Updated: 5/2007
Special Feature
Default is Standard. Choose the selection to meet some special requirements from
Softswitch vendors.
Ex. CBCOM, RNK.
Preferred
Vocoder
The GXW–400x supports up to 5 different Vocoder types including G.711 A-/U-law,
G.726 (Supports bit rates 16, 24, 32 and 40), G.723.1, G.729A/B/E and iLBC. The
user can configure Vocoders in a preference list that will be included with the same
preference order in SDP message. The first Vocoder is entered by choosing the
appropriate option in “Choice 1”. The last Vocoder is entered by choosing the
appropriate option in “Choice 8”.
G723 Rate
Defines the encoding rate for G.723 vocoder. By default, 6.3kbps rate is chosen.
iLBC Frame Size Sets the iLBC frame size in 20ms or 30ms
iLBC Payload
type
Defines payload type for iLBC. Default value is 97. The valid range is between 96
and 127.
G726-16 Payload
type
Default value is 98. Range is from 96 to 127.
G726 - 24
Payload type
Default value is 99. Range is from 96 to 127.
G726 - 32
Payload type
Default value is 100. Range is from 96 to 127.
G726 - 40
Payload type
Default value is 103. Range is from 96 to 127.
G729E payload
type
Default value is 102. Range is from 96 to 127.
VAD
Default is No.
VAD allows detecting the absence of audio and conserve bandwidth
by preventing the transmission of "silent packets" over the network.
Symmetric RTP
Default is No.
When set to Yes the device will change the destination to send RTP
packets to the source IP address and port of the inbound RTP packet last received
by the device.
Fax Mode
T.38 (Auto Detect) FoIP by default, or Pass-Through (must use codec
PCMU/PCMA)
Fax Tone
Detection Mode
Default is Callee.
This decides whether Caller or Callee sends out the re-INVITE
for T.38 or Fax Pass Through.
Jitter Buffer Type Select either Fixed or Adaptive based on network conditions.
Jitter Buffer
Length
Select Low, Medium or High based on network conditions.
SLIC Setting
Dependent on standard phone type (and location)