Grandstream Networks GXV3275 Administration Manual page 54

H.264 Payload Type
SRTP Mode
SRTP Encryption Bit
Silence Suppression
Voice Frames Per TX
Jitter Buffer Maximum (ms)
Firmware Version 1.0.3.6
The default setting is "Media Level".
Note:
Please do not modify this setting without knowing the session format
supported by the server. Otherwise, it might cause video decoding
failure.
It is used to configure the H.264 codec message payload type format.
The default setting is 99. The valid range is from 96 to 127.
It is used to set if the phone system will enable the SRTP (Secured RTP)
mode. It can be selected from dropdown list:

Disable

Enabled but not forced

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".
It is to configure all the AES (Advanced Encryption Standard) key size
within SRTP. It can be selected from dropdown list:

AES128&256 bit

AES 128 bit

AES 256 bit
If it is set to "AES 128&256 bit", the phone system will provide both AES
128 and 256 cipher suite for SRTP. If set to "AES 128 bit", it only
provides 128 bit cipher suite; if set to "AES 256 bit", it only provides 256
bit cipher suite. The default setting is "AES128&256 bit".
It is used to set 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".
It is used to set 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.
It is used to define the amount of delay to eliminate jitter caused by
GXV3275 Administration Guide Page 52 of 103