Patent attributes
A communication terminal is connected to a server and provides movement guidance for a mobile unit based on guidance information delivered from the server. The terminal requests the server for update information for updating area identification information that identifies a section corresponding to an update target area and a section not corresponding to the update target area on a section-by-section basis. The update target area is an area whose terminal-side map information included in the communication terminal is an older version. The terminal updates the area identification information based on the update information transmitted from the server, requests the server for guidance information for providing movement guidance for the mobile unit based on the updated area identification information, and provides the movement guidance for the mobile unit based on the guidance information delivered from the server.