Map difference data delivery system, map difference data delivery device, map data holding device, update management server, and map difference extraction server

A system for updating a map in a navigation device of a vehicle, the system comprising:

• a map difference data delivery device including a map difference extraction server having a map difference database, wherein the map difference database stores map difference data representing a difference between a version of map data after updating map elements and a version of the map data before updating the map elements, wherein the map difference extraction server delivers the map difference data to the navigation device;
• and
• the navigation device, wherein the navigation device includes a communicator in communication with the map difference extraction server of the map difference data delivery device, a position detector configured to detect a position of the navigation device, a map database that stores the map, a display device configured to display the map, and a controller having a different data acquisition portion configured to acquire the map difference data from the map difference extraction server of the map difference data delivery device through the communicator, and an update portion, the update portion configured to update the map stored in the map database and used in the navigation device based on the map difference data delivered from the map difference extraction server through the communicator and received by the different data acquisition portion of the controller,
• wherein
• in addition to data of the map elements updated in the version, the map difference data stored in the map difference database includes data of dependent map elements by dating back to update of map elements corresponding to a different version, wherein the dependent map elements are map elements that have a dependent relationship and need to be previously updated to avoid conflict with other map elements when updated,
• wherein the map difference data delivery device further includes:
• an update management server that extracts non-updated data from the map difference data stored in the map difference database, wherein the non-updated data is data of map elements not yet updated in the navigation device;
• and wherein the map difference extraction server groups data of the dependent map elements that have the dependent relationship in the same version,
• generates delivery data by arranging records to comply with specified communication traffic, wherein the delivery data is data to be delivered by the map difference extraction server, wherein each record is a collection of the non-updated data grouped by the map difference extraction server, and
• delivers the map difference data to the navigation device through the communicator by delivering the delivery data to the navigation device through the communicator,
• wherein the update portion of the controller updates the map in the navigation device based on the delivered map difference data, and
• wherein the display device displays the map, updated by the update portion of the controller based on the delivered map difference data, to provide navigation guidance to a user of the navigation device of the vehicle.