| 摘要 |
PROBLEM TO BE SOLVED: To make it possible that, even when one inputs a password to use a card, others can hardly read the password by watching and an existing device can be used as it is, for the realization of such device at a low cost. SOLUTION: When a card is registered, a unique password is registered and it is also made possible to register a clear character string that neglects an input character string. The password and the clear character string are linked to the card number and are held in a host computer. If the clear character string is a '98' composed of a two-digit number, and the password is registered as a '1234' composed of a four-digit number, a '1583' inputted before the clear character string '98' is totally neglected, and thus a dummy input can be performed. Because it is devised to identify a four-digit character string that is inputted just after the clear character string '98' as the password, '1234' can be identified as the password. A '67' inputted after the password is neglected and treated as a dummy input. |
