| 摘要 |
PROBLEM TO BE SOLVED: To provide a means for holding security high even if the number of terminals increases and management becomes difficult. SOLUTION: The system is provided with an IC card 1 holding more than two memory areas, a first key 4 having authority to read/write a first memory area and a second memory area among the memory areas and a second key 5 having authority to read/write only the second memory area, with a first terminal 2 holding only the first key 4 and with the second terminal 3 holding only the second key 5. Thus, the IC card system of high security can be provided by writing the same data in the first memory area and the second memory area of the IC card 1 in the first terminal 2 and adding or subtracting data of the second memory area in line IC card 1 in the second terminal 3. |
