| 摘要 |
PROBLEM TO BE SOLVED: To make a certificate issued for a contribution act using points inalterable in an electronic mall system adopting a point system. SOLUTION: This point management system is formed by an information management device for managing the information on the point system for giving points to a user according to the degree of trade, and returning service depending on the accumulation number of points to the user, and an electronic device connected to the information management device through the network to communicate with each other, and the contents given and taken between the information management device and the electronic device and recorded in the information management device are enciphered. |
