Grandstream Networks GVC3200 Administration Manual page 44

It
GVC3200/GVC3202 is acted as a callee. If set to "Caller", the device will negotiate
Codec
Negotiation
codec by SDP codec sequence from the received SIP INVITE message. If set to
"Callee", the device will negotiate codec according to the codec priority configuration
Priority
on the device itself. The default setting is "Callee".
It is used to set the silence suppression/VAD feature. If it is set to "Yes", when
Silence silence is detected, a small quantity of VAD packets (instead of audio packets) will
Suppression be sent during the period of no talking. If set to "No", this feature is disabled. The
default setting is "No".
It should be noted that the "ptime" value for the SDP will change with different
configurations here. This value is related to the codec used and the actual frames
transmitted during the in payload call. e.g.: if set to 2 and the first codec is G.729,
Voice Frames Per G.711 or G.726, the "ptime" value is 20ms for the SDP. If the TX exceeds the
TX maximum allowable value, the device will use and save the maximum allowed value
according to what the first codec is. For end users, it is recommended to use the
default setting, as incorrect settings may influence the audio quality. The default
setting is "2".
It is used to select encoding rate for G.722.1 codec. It supports 24kbps or 32kbps.
G.722.1 Rate
The default setting is "24kbps encoding rate".
G.722.1 Payload It is used to configure payload type for G.722.1 codec. The valid range is 100-126.
The default setting is "104".
Type
Opus Payload It is used to configure payload type for Opus codec. The valid range is 96-126. The
default setting is "123".
Type
Use First Matching
If set to "Yes", the device will use the first matching vocoder in the sent 200OK SDP
Vocoder in 200OK
as the codec. The default setting is "No".
SDP
If set to "Yes", the RFC5168 mechanism will be enabled for video call. RFC5168
Enable RFC5168
allows SIP party to request the sender to refresh its video frame in H.264, or refresh
Support
the full picture in VP8. The default setting is "Yes".
If enabled, the video sender will temporarily allocate part of the bandwidth to one
data channel to send FEC data to system, thus to improve the video quality the
Enable Video FEC
receiver gets. Enabling this function will take up part of bandwidth and reduce call
rate. The default setting is "Yes".
If set to 0, FEC is not sent by separate port. If set 1, FEC is sent by separate port.
Video FEC Mode
Default setting is 0.
It is used to configure FEC payload type. The range is 96-127. The default setting is
FEC Payload Type
120.
FEC RED Payload It is used to configure FEC RED payload type. The valid range is from 96 to 127.
Type The default value is 122.
Firmware Version 1.0.1.48
www.voipon.co.uk sales@voipon.co.uk Tel: +44 (0)1245 808195 Fax: +44 (0)1245 808299
is used to configure
GVC3200/GVC3202 Administration Guide
the codec negotiation sequence when the
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