- Interconnect two PBXs at separate sites through IP network with FXO gateways
- Interconnect two or more extension lines at separate sites through IP network with FXS gateways
- Expanding PBX extensions to remote sites through IP network
In this application note, the third one popular application and related configurations are described.
In this scenario, a PBX located at different site need to be interconnected through IP network to expand PBX extension lines.
In this diagram, the FXO gateway is installed with the FXO ports connecting to the extension ports of the PBX while FXS gateway is installed with the FXS ports connecting to analog phones. WAN ports are connected to the router in the local office. Both gateways are interconnected over the IP network with SIP protocol in peer-to-peer mode for call setup.
Note: A static public IP address is required if the IP network is Internet.
Configuration on FXO Gateway
1.On the Basic > SIP page, fill in FXS gateway’s IP address in the Proxy Server field, as follows:
2.On the Basic > System page, select RFC2833 in the DTMF method filed , as follows:
3.On the Line > Trunk, select Binding in the Inbound handle field, and fill in the corresponding phone number of the FXS port in the Binding number field, as follows:
Configuration on FXS Gateway
1.On the Basic > SIP page, fill in FXO gateway’s IP address in the Proxy Server field, as follows:
2.On Basic > System, same as we did on FXO gateway.
3.On the Line > Feature, select Hot Line in the Hot line field, and fill in the corresponding FXO port number in the Hot line number field, as follows:
With FXO-FXS hot line arrangement as described in the above configurations, there is no need to use routing table.