Grandstream Networks HT503 User Manual page 63

Payload Type
AAL2-G726-32
Payload Type
AAL2-G726-40
Payload Type
G729E Payload Type
VAD
Symmetric RTP
Fax Mode
Fax Tone Detection
Mode
Jitter Buffer Type
Jitter Buffer Length
SRTP Mode
Crypto Life Time
from 96 to 127.
Defines payload type for AAL2-G726-24. Default value is 104. Range is
from 96 to 127.
Defines payload type for AAL2-G726-40. Default value is 103. Range is
from 96 to 127.
Defines payload type for G729E. Default value is 102. Range is from 96 to
127
Default is No. VAD allows detecting the absence of audio and conserves
bandwidth by preventing the transmission of "silent packets" over the
network.
Default is No. When set to "Yes" the device will change the destination to
send RTP packets to the source IP address and port of the inbound RTP
packet last received by the device.
T.38 (Auto Detect) FoIP by default, or fax Pass-Through (must use
PCMU/PCMA)
Default is Callee. This decides whether Caller or Callee sends out the re-
invite for T.38 or Fax Pass-Through.
Select either Fixed or Adaptive based on network conditions.
Select Low, Medium, or High based on network conditions.

High (initial 200ms, min 40ms, max 600ms) Note: not all vocoders
can meet the high requirement

Medium (initial 100ms, min 20ms, max 200ms)
Low (initial 50ms, min 10ms, max 100ms)
Secure RTP protocol used for media transmission over VoIP. Disabled by
default. Other modes are: enabled but not forced & enabled and forced.
Default is Enabled. Allows user to enable or disable Crypto life time when
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