Grandstream Networks HT812 Administration Manual page 37

Fax Mode Specifies the fax mode: T.38 (Auto Detect) FoIP by default, or Pass-Through. If using Pass-through mode, select
preference codec as PCMU or PCMA.
Re-Invite
Permits the unit to send out the re-INVITE for T.38 or Fax Pass Through if a fax tone is detected. Default
after Fax
Tone is Enabled
Detected
Jitter
Buffer Selects jitter buffer type (Fixed or Adaptive) based on network conditions.
Type
High (initial 200ms, min 40ms, max 600ms) Note: not all vocoders can meet the high requirement.
Jitter
Buffer Medium (initial 100ms, min 20ms, max 200ms).
Length
Low (initial 50ms, min 10ms, max 100ms).
Selects SRTP mode to use ("Disabled", "Enabled but not forced", or "Enabled and forced"). Default is Disabled
SRTP It uses SDP Security Description to exchange key. Please refer to
Mode
SDES: https://tools.ietf.org/html/rfc4568
SRTP: https://www.ietf.org/rfc/rfc3711.txt
Allows users to select supported SRTP Key Length. the available values are :
1. AES 128&256 bit
SRTP Key
2. AES 128 bit
Length
3. AES 256 bit
Set to AES 128&256 bit By Default.
Crypto
Adds crypto life time header to SRTP packets. Default is Yes.
Life Time
SLIC
Depends on standard phone type (and location).
Setting
Caller ID
Selects the caller id scheme, for example: Bellcore/Telcordia, ETSI-FSK ...
Scheme
DTMF
Defines the start and stop tones (Default, A, B, C, D or #) to delimit CID.
Caller ID
Disable analog phone's caller ID when receiving a call with "Anonymous", "unavailable" or "unknown" in FROM
Disable
header and without "Display info".
Unknown
Note: This relies also on analog phone's design, some phones will still display "unknown" with this feature
Caller ID
enabled. Default is No.
Replace
Beginning
When this feature is set to Yes, device will replace the "+" sign at the beginning of a number in the
'+' with
FROM header. Default is No.
00 in
Caller ID
Reverses the polarity upon call establishment and termination.
Polarity
Reversal
Default is No.
Loop
Allows the traditional PBX used with HT81x to apply this method for signaling call termination. Method initiates
Current
Disconne short voltage drop on the line when remote (VoIP) side disconnects an active call. Default is No.
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