| 摘要 |
<p>PROBLEM TO BE SOLVED: To use a portable terminal as a medium of a key.SOLUTION: A portable terminal 2 holds record of a password PIN in advance, and transmits the password PIN with an issue request for key data to a key distribution server 3. When the key distribution server 3 receives the issue request for the key data, the key distribution server 3 generates the key data by attaching a signature generated from control authority information, a secret key and the password PIN to the control authority information, and distributes the generated key data to the portable terminal 2. A control device 4 requests the key data from the portable terminal 2 in a communicable area. In response to the request for the key data from the control device 4, the portable terminal 2 transmits the key data received from the key distribution server 3 and the password PIN held by the portable terminal 2 to the control device 4. The control device 4 generates a signature from the key data and password PIN received from the portable terminal 2 and the secret key, and when the generated signature and the signature included in the key data received from the portable terminal 2 match each other, the control device 4 normally authenticates the key data.</p> |
