Grandstream Networks HT812 Administration Manual page 51

VAD
Symmetric RTP
Fax Mode
Re-Invite after Fax Tone
Detection Mode
Jitter Buffer Type
Jitter Buffer Length
SRTP Mode
Crypto Life Time
SLIC Setting
Caller ID Scheme
DTMF Caller ID
Polarity Reversal
Loop Current Disconnect
Play busy/reorder tone before
Loop Current Disconnect
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
Adds crypto life time header to SRTP packets. Default is Yes.
Depends on standard phone type (and location).
Selects the caller id scheme, for example: Bellcore/Telcordia, ETSI-FSK ...
Defines the start and stop tones.
Reverses the polarity upon call establishment and termination.
Default is No.
Allows the traditional PBX used with HT812/HT814 to apply this method for
signaling call termination. Method initiates short voltage drop on the line when
remote (VoIP) side disconnects an active call. Default is No.
Allow user to configure if it will play busy/reorder tone before loop current
disconnect upon call fail.
Default is No.
HT812/HT814 Administration Guide
Version 1.0.9.3
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