A public land mobile network (PLMN)/private wireless network-integrated service network and a system for the service network. The service network according to the present invention can interwork with any PLMN with no dependence on an upper system. In the present invention, there is no need for a public BSC and a separate private BSC. The novel BSC handles both public and private data and voice calls placed from or placed to a mobile station or terminal. The novel BSC enables a wireless phone or terminal to place and receive calls using either the public communications network or the private communications network. Thus, the need for a redundant private BSC is eliminated while providing the diversity of services to mobile stations.