| 摘要 |
PROBLEM TO BE SOLVED: To confirm or prove that position-time information is legitimate information really measured in a portable apparatus with a GPS reception function which is actually used by a user. SOLUTION: An information apparatus includes a secret key holding part 122 for holding a secret key which differs between apparatuses, and an identification information holding part 115 for holding identification information of the apparatus or identification information of the user of the apparatus. The position-time information, which is measured based on radio wave received from a positioning satellite and indicates the reception position and time of the radio wave, is digitally signed in a digital signing means 121 through the use of the secret key held by the secret key holding part 122. The identification information held in the identification information holding part 115 and the position-time information with the digital sign added thereto are transmitted to a communication opposite party. COPYRIGHT: (C)2010,JPO&INPIT |
