| 摘要 |
<p>PURPOSE:To make hard a trial input and to improve the secrecy of a password by executing the writing processing to make the information to show an error condition into the same as an original storing information or to make it into the original information as it is, in the same timing as an error time even when the inputted password is correct. CONSTITUTION:At an IC card 10, a meaningless signal or a current signal are outputted for an IC card reader writer 11 by the generation timing of a password re-inputting signal when the password is erroneous when it is correct after the password is received and collated, and when the password is erroneous, a password re-inputted signal is sent to the IC card reader writer 11. When the number of the times of errors goes to the prescribed number of times set beforehand, and even when the correct password is inputted, the writing to update or not to update and error control flag 62 is executed. Thus, the condition which is erroneous or the condition which is not erroneous cannot be discriminated with the signal detecting watched from an external part and the password cannot be decoded.</p> |
