Administration Guide

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WP820 Administration Guide
Version 1.0.5.5
Priority
When set to "Caller", the phone negotiates by SDP codec sequence from received
SIP Invite; When set to "Callee", the phone negotiates by audio codec sequence
on the phone.
Use First Matching
Vocoder in 200OK
SDP
Includes only the first matching vocoder in its 200OK response, otherwise it will
include all matching vocoders in same order received in INVITE.
The default setting is No.
iLBC Frame Size
Specifies iLBC packet frame size (20ms or 30ms). Default is 30ms.
Opus Payload Type
Determines payload type for Opus codec. The valid range is between 96 and 126.
Default is 123.
DTMF
Specifies the mechanism to transmit DTMF (Dual Tone Multi-Frequency) signals.
There are 3 supported modes:
• 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".
DTMF Payload Type
Configures the RTP payload type using RFC2833 that indicates the transmitted
packet contains DTMF digits. Valid range is from 96 to 127.
Default value is 101.
Enable Audio RED
with FEC
If set to "Yes", FEC will be enabled for audio call.
The default setting is "No".
Audio FEC Payload
Type
Configures audio FEC payload type. The valid range is from 96 to 127.
The default value is 121.
Audio RED Payload
Type
Configures audio RED payload type. The valid range is from 96 to 127.
The default value is 124
Silence Suppression
Enables the silence suppression/VAD feature. If it is set to “Yes”, when silence is
detected, a small quantity of VAD packets (instead of audio packets) will be sent
during the period of no talking. If set to “No”, this feature is disabled.
The default setting is “No”.