Eusso 2 & 4 Port VoIP Gateway, User Manual

Page: 61 / 112

ITG User’s Guide
Application B: FXS / FXO combination
Application-B has three possible connections. The B-1 connection is a normal trunk connection
between the CO switch and PBX. The B-2 connection is identical to the A-1 connection
mentioned in Application A. The B-3 connection is used to connect the PBX and gateway
through the internal analogue lines provided by the PBX. In this case, the FXO module has to be
used, and the FXO ports will serve the same roles as the analogue telephone sets.
Note: If the PBX used in the B-3 connection is a digital type, a certain analog terminal
adapter is needed to provide an analog interface to the FXO module.
In this application, The caller in the B-2 connection can use the Gateway through its FXS
module to communicate with the party on the other end in the B-3 connection. The phone call is
forwarded through the FXS module in the B-2 Gateway and is received by the FXO module in
the B-3 gateway, which is connected to the PBX, which will then switch to the dedicated
terminal.
The same caller can also use the feature that the Gateway provides to redial the local number
through the PBX, to the public switch, in order to reach the person inside the region that the
public switch serves.
Connection B-2
Telephone
Fax
FXS
FXS
IP
Telephone
Connection B-3
Fax
Trunk
Connection B-1
Telephone
Fax
Public Switch
FXO
PBX
Telephone
Making a Call with ITG
49