Codec Settings - Grandstream Networks GSC3510 Series User Manual

Sets the callee party to act as refresher by force. If set to "Yes" and the both parties support session timers, the device will enable
Callee Request
the session timer feature when it receives inbound calls. The SIP 200 OK will include the content "refresher=uas". The default
Timer
setting is "No".
Configures the session timer feature on the device by force.
If it is set to "Yes", the device will use the session timer even if the remote party does not support this feature.
Force Timer
If set to "No", the device will enable the session timer only when the remote party supports this feature. To turn off the
session timer, select "No".
The default setting is "No".
Sets the SIP message type for refresh the session. If it is set to "Yes", the Session Timer will be refreshed by using the SIP INVITE
Force INVITE
message. Otherwise, the device will use the SIP UPDATE or SIP OPTIONS message. Default is "No".

Codec Settings

Preferred Vocoder
Preferred Vocoder
Codec Negotiation Priority
Use First Matching Vocoder in 200OK
SDP
iLBC Frame Size
G726-32 ITU Payload Type
G726-32 Dynamic Payload Type
Opus Payload Type
DTMF
DTMF Payload Type
Enable Audio RED with FEC
Audio FEC Payload Type
Lists the available and enabled Audio codecs for this account. Users can enable the specific audio codecs by moving them to
the selected box and set them with a priority order from top to bottom. This configuration will be included with the same
preference order in the SIP SDP message.
Configures the device to use which codec sequence to negotiate as the callee. When set to "Caller", the device negotiates by
SDP codec sequence from received SIP Invite; When set to "Callee", the device negotiates by audio codec sequence on the
device. The default setting is "Callee".
Configures the device to use the first matching codec in the 200OK message. The default value is 0.
Sets the iLBC (Internet Low Bitrate Codec) frame size if ILBC is used. Users can select it from 20ms or 30ms. The default
setting is 30ms.
Configures G726-32 payload type for ITU packing mode. Payload 2 is static and payload dynamic is dynamic. The default
setting is "2".
Specifies the G726-32 payload type, and the valid range is 96 to 127. The default setting is "126".
Defines the desired value (96-127) for the payload type of the Opus codec. The default value is 123.
Specifies the mechanism to transmit DTMF (Dual Tone Multi-Frequency) signals.
There are 3 supported modes: in audio, RFC2833, or SIP INFO.
• In audio, which means DTMF is combined in the audio signal (not very reliable with low-bit-rate codecs);
• RFC2833, which means to specify DTMF with RTP packet. Users could know the packet is DTMF in the RTP header as well
as the type of DTMF.
• SIP INFO, which uses SIP INFO to carry DTMF. The defect of this mode is that it's easily to cause desynchronized of DTMF
and media packet if the SIP and RTP messages are required to transmitted respectively.
The default setting is "RFC2833".
Configures the RTP payload type that indicates the transmitted packet contains DTMF digits. Valid range is from 96 to 127.
Default value is 101.
If set to "Yes", FEC will be enabled for audio call. The default setting is "No".
Configures audio FEC payload type. The valid range is from 96 to 127. The default value is 121.