| 摘要 |
PURPOSE:To improve the safety by sending two different encipherment keys to a transaction device through different routes and generation a new encipherment key therein by using these encipherment keys. CONSTITUTION:A first encipherment key is stored in a host computer 11, a storage means 17 for storing a second encipherment key and an encipherment algorithm and an enciphering means 15 are provided, and also, an IC card 14 which can be connected to a transaction device 12 is provided. The transaction device 12 sends out a first encipherment key to the IC card 14, the enciphering means 15 of the IC card 14 generates a third encipherment key from a first encipherment key, based on a second encipherment key and an encipherment algorithm, the transaction device 12 sends out a third encipherment key to an input device 13, and the input device 13 enciphers confidential information, based on a third encipherment key and the encipherment algorithm and sends it out to the transaction device 12. In such a way, since the confidential information is enciphered by generating a new encipherment key and using it, it is excellent in safety. |
