Patent attributes
A navigation device performs a route guidance based on a route from a current location to a destination. A communication controller sends a request for searching the route to a server. A guidance-information receiving unit receives information on the route from the server. A time measuring unit measures an elapsed time from a start of the route guidance. A guidance controller performs the route guidance based on the information received. The communication controller commands the navigation device to cut off a communication with the server and to stand by upon a determination that the elapsed time measured has reached a predetermined time and when the route is being guided or a current location is being checked by the guidance controller, to decrease a bandwidth usage between the navigation device and the server and to reduce a communication charge associated with the bandwidth usage.