| 摘要 |
PURPOSE:To reduce danger that a password is known and a resource to be protected is stolen by decoding the whole of a part of the passwords based on a random number table, and changing the content of the random number table at every use request. CONSTITUTION:When there is the use request of the resource to be protected, the random number table is displayed to person who has requested the use. The random number table is appropriately changed whenever there is the use request. Then the whole or a part of the passwords are decoded from the displayed random number table by using a previously registered cipher decoding method, and the password with respect to the person who has requested the use is generated. On the other hand, a user decodes the whole or a part of its own passwords and can generate the prescribed passwords. When the passwords which the person who has requested the use coincides with the passwords generated in the device, the person who has requested the use can judges to be the right user. |
