Abstract: A CPU of a navigation apparatus stores public keys to which priorities are set and which are published by an information distribution center in a public key storage section. The CPU of the navigation apparatus extracts an electronic signature of distribution data which is distributed from the information distribution center and verifies the electronic signature by using only ‘valid’ public keys among the public keys in order of the priorities. The CPU of the navigation apparatus determines that the distribution data is valid information which is distributed from the information distribution center when the electronic signature passes verification.

Abstract: Map updating systems, methods, and programs that store map information, including one or more pieces of difference update information, obtain the one or more pieces of difference update information used for updating a part of the map information, and update the map information based on the one or more pieces of difference update information. The systems, methods, and programs obtain total update information used for updating an entirety of the memory to a new piece of map information, update the map information based on the total update information, compare a version of the total update information used in the total update with each of versions of the one or more pieces of difference update information stored in the memory, extract any of the one or more pieces of difference update information judged to be newer and update the map information based on the difference update information.

Abstract: A map update data supply apparatus includes: isolation detection means (8) for detecting the presence and the absence of an isolated state in which some of the roads are isolated from other roads in a road network of target map data due to updating of one or more update target segments of the target map data based on update map data (Ma); extraction means (9) for extracting, as update required segments, segments of the update map data (Ma), other than the update target segments, that have a road that connects to the isolated some of the roads when it is detected that there is the isolated state; and update data file generating means (10) for generating update data files (fa) for the update target segments and the update required segments based on the update map data (Ma).

Abstract: Map information distribution systems and methods store map information and version information for each road category of the map information stored in a navigation device, the version information correlated with identification information identifying the navigation device. The systems and methods receive the identification information from the navigation device and obtain, based on the received identification information, the version information for each road category of the map information stored in the navigation device corresponding to the stored identification information. The systems and methods extract, based on the obtained version information for each road category, differential data for each road category with stored map information of a latest version, and transmit the extracted differential data for each road category to the navigation device corresponding to the received identification information.

Abstract: Map information distribution systems, methods, and programs that update map information based and distribute the update information, send update request information for requesting the update information of the map information, receive the update request information, and obtain the update information corresponding to the received update request information. The systems, methods, and programs obtain updated content corresponding to the obtained update information, assign a score to the updated content based on factor information corresponding to the obtained updated content, assign an order of priority to the respective updated content based on the scores assigned to the respective updated content, distribute the update information and the prioritized updated content, update the map information based on the received update information, and notify a user of the received updated content based on the order of priority assigned to the updated content.

Abstract: Map updating systems, methods, and programs that extract update requiring sections with respect to an update requesting section that is one of the sections being a target of an update request requesting that the target map data should be updated, obtain the information related to the guaranty versions respectively corresponding to the extracted update requiring sections by referring to the version table, the update requiring sections each being one of the sections that needs to be updated in order to guarantee integrity between the sections that are positioned adjacent to each other after the update requesting section has been updated, and generate, based on the update-purpose map database, one of the update data files regarding the update requesting section as well as other ones of the update data files regarding the update requiring sections and having the update versions indicated as the guaranty versions.

Abstract: To provide a data updating system and the like for easily performing updating the difference for the database which contains a large amount of data, each piece of the data being highly correlated, such as a map database that contains road network data. According to the present invention, the data updating system includes a terminal device running according to a predefined operating program, and servers providing the terminal device with a differential data file for updating a database. The terminal includes a local database in an updating data format differing from a reference data format to be referenced to by the operating program and being updated with the differential data file, and a conversion means converting data stored in the local database so as to have the reference data format. The servers include a differential data file output means outputting the differential data file to be provided to the terminal device.

Abstract: A map updating system that stores map data and a priority sequence table, acquires first update data and second update data of the map data according to the priority sequence table, and updates the map data based on the first update data and second update data according to the priority sequence table.

Abstract: When the navigation apparatus 5 performs a difference update on navigation map data 39 based on difference update data 17 distributed from a map distribution center 2, the difference update data 17 used in the difference update is stored into a navigation HDD 32, when the navigation apparatus 5 performs a total update on the navigation map data 39 thereafter, the navigation apparatus 5 performs a difference update again (S17) by using any piece of the difference update data stored in the navigation HDD 32 of which the version is newer than that of total update data. After performing the update, the navigation apparatus 5 deletes the pieces of difference update data 17 from the navigation HDD 32 that have been stored up to that point in time (S18).

Abstract: A map information delivery system, including a navigation apparatus, is capable of preferentially receiving map updating information based on a host vehicle's state. The updating information may be preferentially received based on whether a destination has been set, a location of the updating information relative to an updating position or a destination, and/or the size of the updating information.