Grandstream GXW42xx User Manual User Manual
Page 49
FIRMWARE 1.0.5.8
GXW42XX USER MANUAL
PAGE 47 OF 62
Preferred Vocoder The GXW42XX 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, 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”.
Voice Frames per
TX
Number of the frame size when it transmits. Default is 2, from 1 -4 for G711/G726/G729
G723 Rate
Defines the encoding rate for G.723 vocoder. By default, 6.3kbps rate is chosen.
G726-32 Packing
Mode
Choose the packing mode for G726-32
iLBC Frame Size
Sets the iLBC frame size in 20ms or 30ms
iLBC Payload type Default value is 97.Defines payload type for iLBC. The valid range is between 96 and 127.
AAL2-G726-16
Payload type
Default value is100. Range is from 96 to 127.
AAL2-G726-24
Payload type
Default value is 99. Range is from 96 to 127.
AAL2-G726-32
Payload type
Default value is 104. Range is from 96 to 127.
AAL2-G726-40
Payload type
Default value is 103. Range is from 96 to 127.
Use First
Matching Vocoder
in 200OK SDP
Default is No
. If set to “Yes”, device will include only the first match vocoder in its 200OK
response, otherwise it will include all match vocoders in same order received in INVITE.
SRTP Mode
Default is Disabled. Other options are Enabled but not forced, and Enabled and forced.
It uses SDP Security Description to exchange key. Please refer
SDES
SRT
Silence
Suppression
(VAD)
Default is No. VAD allows detecting the absence of audio and conserve bandwidth by
preventing the transmission of "silent packets" over the network.