48
Item
Description
Preferred Codec Type
Since different voice codec have different compression ratios,
so the sound quality and occupied bandwidths are also
different. It is recommended to use the default provided
(G.723.1) because it occupies less bandwidth and will provide
better sound quality.
Jitter Buffer
VoiceCom90 sends the same FAX frame twice to get a high
quality of the FAX. It requires more bandwidth.
Silence Detection/Suppression
VoiceCom90 uses T.30 as the protocol for fax transmission.
The parameter settings are the same as for voice transmission.
However, enabling the fax function will consume more
network resources and will affect transmission quality.
Echo Cancellation
Adjust the sensitivity of detection as to whether a phone call is
a FAX or not.
Packet Time
Defines how long VoiceCom90 sends a RTP packet-voice
packet- to the other side. The smaller the value, the more
bandwidth usage. The larger the value, the more voice delay.
Approximate Bandwidth Require
The bandwidth required varies with codec format and packet
time.
Line Settings
VC-91-1 VC-91-2 VC-92-1 VC-92-2 VC-92-3
PSTN Busy-Out With FXS Pick-Up
V
x
V
x
x
PSTN Answer Detection
x
x
x
x
V
Force Calling Thru PSTN Code
V
x
V
x
V
FXO Impedance
V
x
V
x
V
