| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an authentication system using position information that can effectively prevent unauthorized use by means of the position information acquired from a portable terminal device owned by a user, such as a cellphone. <P>SOLUTION: An authentication server 30 comprises a position history saving means for saving position information from the portable terminal device, an authentication request storage means for storing an authentication request from a service requester terminal device 50 which includes first position information and user information, a portable terminal position extraction means for recognizing the portable terminal device by the user information and extracting second position information about the corresponding portable terminal device from the position history saving means, a route search means for searching for a route of movement between two points on the point and time of the first position information and the point and time of the second position information, and an authentication means. The authentication means results in successful authentication if the route search means can find a route of movement between the two points within the time difference, or if not, results in unsuccessful authentication. <P>COPYRIGHT: (C)2008,JPO&INPIT |
