User manual
FIRMWARE VERSION 1.0.14.1 HT503 USER MANUAL Page 47 of 64
associated with the first vocoder in the above vocoder Preference List or the actual
used payload type negotiated between the 2 conversation parties at run time.
Default is 2, from 1 to 4 for G711/G726/G729 only
For example: if this field is set to be 2 and if the first vocoder chosen is G729 or G711
or G726, then the “ptime” value in the SDP message of an INVITE request will be 20ms
(2 x10ms)
If the configured voice frames per TX exceeds the maximum allowed value, the ATA will
not accept it and will use and save the precedent configured allowed value for the
corresponding first vocoder choice.
G723 Rate
This defines the encoding rate for G723 vocoder. Default setting is 6.3kbps.
iLBC Frame Size
This sets the iLBC size in 20ms or 30ms
iLBC Payload Type
This defines payload type for iLBC. Default value is 97. The valid range is between 96
and 127.
AAL2-G726-16 Payload
Type
Defines payload type for AAL2-G726-16. Default value is 100. Range is from 96 to
127.
AAL2-G726-24 Payload
Type
Defines payload type for AAL2-G726-24. Default value is 99. Range is from 96 to 127.
AAL2-G726-32 Payload
Type
Defines payload type for AAL2-G726-24. Default value is 104. Range is from 96 to
127.
AAL2-G726-40 Payload
Type
Defines payload type for AAL2-G726-40. Default value is 103. Range is from 96 to
127.
G729E Payload Type
Defines payload type for G729E. Default value is 102. Range is from 96 to 127
VAD
Default is No. VAD allows detecting the absence of audio and conserves bandwidth by
preventing the transmission of “silent packets” over the network.
Symmetric RTP
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.
Fax Mode
T.38 (Auto Detect) FoIP by default, or fax Pass-Through (must use PCMU/PCMA)
Fax Tone Detection Mode
Default is Callee. This decides whether Caller or Callee sends out the re-invite for T.38
or Fax Pass-Through.
Jitter Buffer Type
Select either Fixed or Adaptive based on network conditions.
Jitter Buffer Length
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)