Grandstream Networks HT814 Administration Manual page 40

https://arttel.ru/
Preferred Vocoder
Voice Frames per
TX
G723 Rate
iLBC Frame Size
Disable OPUS
Stereo in SDP
iLBC Payload type
OPUS Payload Type Determines payload type for OPUS. The valid range is between 96 and 127.
VAD
Symmetric RTP
Fax Mode
Re-Invite after Fax
Tone Detection
Mode
Jitter Buffer Type
Jitter Buffer Length
SRTP Mode
https://arttel.ru/shop/voip-shlyuzy/grandstream-ht-814
Configures vocoders in a preference list (up to 8 preferred vocoders) that will be included
with same order in SDP message.
Vocoder types are G.711 A-/U-law, G.722, G.726-32, G.723, G.729, iLBC and OPUS.
Transmits a specific number of voice frames per packet. Default is 2; increases to
10/20/32/64 for G711/G726/G723/other codecs respectively.
Operates at specified encoding rate for G.723 vocoder. Available encoding rates are
6.3kbps or 5.3kbps. Default is 6.3kbps.
Specifies iLBC packet frame size (20ms or 30ms). Default is 20ms.
Disables OPUS stereo in SDP. Default is No.
Determines payload type for iLBC. The valid range is between 96 and 127. Default is
97.
Default is 123.
Allows detecting the absence of audio and conserves bandwidth by preventing the
transmission of "silent packets" over the network. Default is No.
Changes the destination to send RTP packets to the source IP address and port of the
inbound RTP packet last received by the device. Default is No.
Specifies the fax mode : T.38 (Auto Detect) FoIP by default, or Pass-Through (must use
codec PCMU/PCMA).
Permits the unit to send out the re-INVITE for T.38 or Fax Pass Through if a fax tone is
detected. Default is Enabled.
Selects jitter buffer type (Fixed or Adaptive) 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).
Selects SRTP mode to use ("Disabled", "Enabled but not forced", or "Enabled and
forced"). Default is Disabled.
It uses SDP Security Description to exchange key. Please refer to
SDES: https://tools.ietf.org/html/rfc4568
SRTP: https://www.ietf.org/rfc/rfc3711.txt
HT814 Administration Guide
P a g e | 39