Provided is a center device that enables a navigation device to conduct guidance according to a route on the basis of the latest map information, without imposing a heavy load on a communication network. The center device calculates a guide route as a center route on the basis of the latest of the map information and information received from the navigation device, specifies the map information that is available to the navigation device, and calculates a guide route as a navigation route on the basis of the specified map information and the information received from the navigation device. On the basis of the center route and the navigation route, the center device specifies, from the map information, different map information necessary for the navigation device to give guidance on the center route, and transmits the specified map information to the navigation device.