摘要 |
PURPOSE: A public wireless network service method in an apparatus for interfacing a call between local phone network and femto cells is provided to supply in-house radio network service by interworking with an in-house phone network through a WCDMA based IP-PBX(Private Branch eXchange). CONSTITUTION: If an originating call is the originating call to a core network, an interworking device converts the originating call into a SIP-URI originating call depending on the SIP protocol. The interworking apparatus performs the routing of the converted originating call to the core network through a secure IP tunnel. The interworking apparatus converts some SIP signals received form the core network according to a receiving procedure into Iu signal, and performs the routing of the converted Iu signal to a femto cell base station(103). |