A mobile terminal UE accesses a CN and utilizes the Internet via a base station Node-B. When riding an electric train, the mobile terminal UE receives a disembarkation notification and an embarkation notification from a RFID tag writer equipped on a train, and notifies the base station Node-B that the terminal is on-board the train. While on-board the train, the terminal accesses an in-vehicle AP by employing a WLAN, Bluetooth, or similar system, and the in-vehicle AP communicates with the base station Node-B. This configuration enables the in-vehicle AP to handle all of the mobile devices existing on a train in a centralized manner, thereby eliminating the need for each of the mobile devices to individually access the base station Node-B.