Communication system, base station device, gateway device, method for controlling base station device, and method for controlling gateway device, for enabling to connect user terminal to appropriate core network from among plurality of core networks when making or receiving call

摘要

At the time of registration of a base station, the base station reports to a gateway device list information regarding core networks that are to be connected. At the time of call origination from a user terminal, the base station reports to the gateway device, by means of a message of protocol for termination between a base station and a gateway, network identification information that indicates core networks that are to be connected to the user terminal The gateway device transfers a control message from the user terminal to the core networks indicated by the network identification information that was reported. At the time of call connection to the user terminal, the gateway device selects the base station to which paging from the core network is to be transmitted on the basis of the list information reported from the base station at the time of registration.