| 摘要 |
PURPOSE:To secure the single storage information on a confirming device regardless of the number of users by using the exponent congruence arithmetic and the congruence multiplication to verify the relationship among the random numbers, the received information and the open information. CONSTITUTION:A system control unit 3 uses its own secret information and the identification numbers of each user to produce in secret two keys (key 1, key 2) of each user by means of the exponent congruence arithmetic using a prime number as a divisor and distributes these keys directly to each user or after recording them on the recording media 5 and 6. At the same time, the open information used for confirmation of each user is distributed to a verification processing unit 4. At the side of a user card, the random numbers are produced internally after reception of other random numbers. These produced random numbers, the key 1, the random numbers and the user identification numbers are sent to the unit 4 together with the 1st and 2nd information produced by the exponent congruence arithmetic and the congruence multiplication as well as the user identification numbers and the key 2. Then the unit 4 confirms the propriety of users from the relationship between the transmitted random numbers, the received information and the open information. Thus just the common single open information suffices. |
