Grandstream Networks HT881

Check SIP User ID for incoming
INVITE
Checks the SIP User ID in the Request URI of the incoming INVITE; if it doesn’t match the HT841/HT881 SIP
User ID, the call will be rejected. Direct IP calling will also be disabled. The default is No.
Authenticate incoming INVITE
Challenges the incoming INVITE for authentication with SIP 401 Unauthorized message.
Default isNo.
Allow Incoming SIP Messages from
SIP Proxy Only
Checks SIP address of the Request URI in the incoming SIP message; if it doesn’t match the SIP server
address of the account, the call will be rejected.
Default isNo.
Authenticate server certicate
domain
Congures whether to validate the domain certicate when download the rmware/cong le. If it is set to
“Yes”, the phone will download the rmware/cong le only from the legitimate server. The default setting is
“No”.
Trusted domain name list
Supports setting specic domain names and wildcard domain names, wildcard domain names such as
"*.grandstream.com", use "," to separate domain names
Authenticate server certicate chain Veries certicate when communication method is TCP/TLS
Codec Settings
DTMF Settings
Preferred DTMF method Sorts DTMF methods (in-audio, via RTP (RFC2833) or via SIP INFO) by priority.
Inband DTMF Duration
Allows users to cong the Inband DTMF Duration and inter-duration.
The default Duration is 100ms. Valid range: 40-2000 ms.
The default Inter-duration is 50 ms. Valid range: 40-2000 ms.
DTMF Payload Type Denes payload type for DTMF using RFC2833.
Inband DTMF Tx Gain
Adjusts the transmit gain for inband Dual-Tone Multi-Frequency (DTMF) tones during call signaling.
The Valid range is -12-12 db, default is 0
DSP DTMF Detector Duration
Threshold
Allows users to cong the DSP DTMF Detector Duration Threshold.
The default Duration is 30 ms. Valid range: 20-2000 ms.
The default Inter-duration is 30 ms. Valid range: 20-2000 ms.
DSP DTMF Detector Min Level
determines the minimum level of DTMF tones that the DSP DTMF detector can reliably detect, range is -45-0
dBm, default is -25
DSP DTMF Detector Snr
Sets the signal-to-noise ratio threshold for the DSP DTMF detector, determining the sensitivity to distinguish
DTMF tones from background noise in the audio signal.
Range: 0-12, default is 1
DSP DTMF Detector Deviation
Species the allowed frequency deviation from standard DTMF tones that the DSP DTMF detector can
accommodate.
Range: 0-25, default is 25
DSP DTMF Detector Twist
Denes the maximum deviation from ideal tone frequencies allowed for reliable DTMF detection by the DSP.
Range: 0-12dB, default is 5
Disable DTMF Negotiation Uses DTMF order without negotiation. Default is No.
RFC2833 Events Count This feature allows users to customize the count of RFC2833 events. Default is 8.