| 摘要 |
PROBLEM TO BE SOLVED: To prevent map data from being updated illegally. SOLUTION: In the case of updating the map data of a hard disk unit 10, when an input unit 14 instructs forming/registering of an authentication code for authenticating the normal user of the updating map data; a controller 15 performs the encryption transformation of time data detected by a GPS receiver 11 at that time point by first, second systems different from one another, forms a first authentication code, a second authentication code, registers the former with the hard disk unit 10, and announces the latter to a user. The user purchases a DVD-ROM 3 for updating the map in a dealer. The user acquires the first authentication code formed by the reconversion by a certificate authority from the second authentication code announced via the dealer. The DVD-ROM 3 for updating the map is set to a DVD driver 13. When the input unit 14 instructs the map updating and inputs the first authentication code, the controller 15 installs the map data from the DVD-ROM 3 to the hard disk unit 10 when the inputted first authentication code coincides with the first authentication code of the hard disk unit 10. COPYRIGHT: (C)2005,JPO&NCIPI |
