GL-VP-150
User Manual
Copyright © 2009-2011 GigaLink
Page 31 of 37
Proxy-Require
SIP Extension to notify SIP server that the unit is behind the
NAT/Firewall.
USE NAT IP
NAT IP address used in SIP/SDP message. Default is blank.
Disable call-waiting
Default is
No
.
Preferred Vocoder
The GL-VP-150 supports up to 7 different Vocoder types
including G.711 A-/U-law
，
G.723.1, G.726, G.728, G.729A/B,
iLBC. Depending on the product model, some of these
Vocoders may not be provided in standard release.
Users can configure Vocoders in a preference list that will be
included with the same preference order in SDP message. The
first Vocoder in this list can be entered by choosing the
appropriate option in “Choice 1”. Similarly, the last Vocoder in this
list can be entered by choosing the appropriate option in “Choice
7”.
Voice Frames per TX
This field contains the number of voice frames to be transmitted
in a single packet. When setting this value, the user should be
aware of the requested packet time (used in SDP message) as a
result of configuring this parameter. This parameter is associated
with the first vocoder in the above vocoder Preference List or the
actual used payload type negotiated between the 2 conversation
parties at run time. e.g., if the first vocoder is configured as G723
and the “Voice Frames per TX” is set to be 2, then the “ptime”
value in the SDP message of an INVITE request will be 60ms
because each G723 voice frame contains 30ms of audio.
Similarly, if this field is set to be 2 and if the first vocoder chosen
is G729 or G711 or G726, then the “ptime” value in the SDP
message of an INVITE request will be 20ms. If the configured
voice frames per TX exceeds the maximum allowed value, the
GL-VP-150 will use and save the maximum allowed value for the
corresponding first vocoder choice. The maximum value for PCM
is 10(x10ms) frames; for G726, it is 20 (x10ms) frames; for G723,
it is 32 (x30ms) frames; for G729/G728, 64 (x10ms) and 64
(x2.5ms) frames respectively.
G723 Rate
This defines the encoding rate for G723 vocoder. By default,
6.3kbps rate is chosen.
