Patent ID: 8917701

Claim:
A mobile communication method in which a mobile station executes a handover from a cell subordinate to a first radio base station accommodated in a gateway device to a cell subordinate to a second radio base station, the mobile communication method comprising: a step in which the mobile station sends a measurement report including identification information on the cell subordinate to the second radio base station to the first radio base station; a step in which the first radio base station sends a handover request message including the identification information on the cell subordinate to the second radio base station to an IP address of the gateway device; a step in which the gateway device transfers the handover request message to the IP address corresponding to the identification information on the cell subordinate to the second radio base station; a step in which the first radio base station sends a handover request message including the identification information on the cell subordinate to the second radio base station to the gateway device; and a step in which the gateway device sends a predetermined message indicating that a handover via the gateway device cannot be executed to the first radio base station in a case in which the gateway device determines that the handover request message cannot be transferred to the second radio base station, wherein the first radio base station, after having received the predetermined message from the gateway device, sends the handover request message to the mobile switching center.