Map update server, map update system, and car navigation system

摘要

An update information providing server (20) for providing data of an updated portion in map data composed of plural kinds of the data includes: a map data storage unit (24) that stores incremental update data (243) of a difference between the data at a predefined time and newest data, and a data size (244) of the data (243); an update request receiving unit (23) that receives from a user terminal (30) a map data update request including a capacity of a recording medium (12), and priority information for specifying a data kind (210) of data to be preferentially updated; an update order information making unit (22) that makes update order information (50); an update information transmission unit (25) that extracts the data (243) from the unit (24), to make update information including the extracted incremental update data and the information (50), and transmits the made update information to the terminal (30).