Patent ID: 6126071
Filing Date: 2000-10-03
Classification: G06Q,G07F

Abstract:
An IC memory card system comprising a terminal device and an IC memory card connected thereto,the terminal device selecting a key value,calculating a first value based on the key value using a particular calculating method,calculating a second value based on the key value using a different particular calculating method, andsupplying the key value and first calculated value to the IC memory card;the IC memory card calculating a third value and a fourth value using different particular methods based on the key value from the terminal device,comparing the first value received from the terminal device with the calculated third value, andsupplying the calculated fourth value to the terminal device if the compared first and third values are a same value;wherein the terminal device compares the second value calculated by the terminal device with the fourth value supplied from the IC memory card, andprohibits use of the connected IC memory card if the compared values are not the same.