GAC2570 User Manual
Version 1.0.1.23
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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 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”.
Voice Frames Per TX
Configures the number of voice frames transmitted per packet. When
configuring this, 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. For end
users, it is recommended to use the default setting, as incorrect settings
may influence the audio quality.
The default setting is 2.
RTP Settings
SRTP Mode
Sets if the device will enable the SRTP (Secured RTP) mode. It can be
selected from dropdown list:
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Disable
•
Enabled but not forced
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Enabled and forced
SRTP uses encryption and authentication to minimize the risk of denial of
service. (DoS). If the server allows to use both RTP and SRTP, it should
be configured as “Enabled but not forced”. The default setting is “Disable”.
SRTP Key Length
Configures all the AES (Advanced Encryption Standard) key size within
SRTP. It can be selected from dropdown list:
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AES128&256 bit
,
AES 128 bit
or
AES 256 bit
If it is set to “AES 128&256 bit”, the device will provide both AES 128 and