Terminal unit for providing VoIP service between one private network and the other private network, interworking system and method thereof

摘要

A terminal apparatus for providing a VoIP service between one private network and another private network, an interlocking system and a method thereof are provided to supply a VoIP service without implementing an application layer gateway technique between different networks based on a packet using different private addresses. Another network(200) is the first private network based on a packet using a different private address from one network(400). Another network could be an ADSL(Asymmetric Digital Subscriber Line) network, a W-LAN(Wireless Local Area Network) and a cable network. One network is the second private network in which an interlocking system is constructed. A CS(Circuit Switching) network and a PS (Packet Switching) network are overlapped in one network. A packet-switched type terminal device(100) is a wire/wireless terminal based on a packet, connected to another network. The packet-switched type terminal device provides a VoIP service based on an SIP(Session Initiation Protocol).