| 摘要 |
PROBLEM TO BE SOLVED: To discriminate a forged IC card when it is used. SOLUTION: A magnetic stripe is formed at a part of an IC card and jitters generated on the magnetic stripe are used as a random pattern. Or, a fault position of a memory cell, which is generated when the IC card is manufacture is used as a random pattern, or the electric analog quantity of the memory cell of the IC card is used as a random pattern, thus providing three methods. Any method codes and records information regarding the random pattern on the IC card and when the IC card is used, a terminal device observes and compares its random pattern with the information obtained by decoding the recorded information, thereby deciding the legitimacy of the card. Consequently, even if IC cards are forged, very few that can be used as legitimate cards, so that an illegal actor can not obtain profit by forgery. |
