| 摘要 |
In an IC card having an update function of transaction data, account type, supplementary amount, and valid date are input to the IC card. The IC card adds a renewal number data held therein to the input transaction data, and the data is encrypted using key data, thus generating reference confirmation data. Input confirmation data is generated using the identical encryption generation algorithm by a host system of a credit company. The input confirmation data is supplied to the IC card. A comparison means in the IC card compares the input confirmation data with the generated reference confirmation data. As a result of the comparison, if these data coincide each other, the input data is stored in the memory in the IC card as new transaction data and update processing is executed. |
