| 摘要 |
PROBLEM TO BE SOLVED: To improve the security of a telegraphic message communicated between transmitting and receiving sides in the case of executing an electronic transaction between the transmitting and receiving sides. SOLUTION: A terminal equipment 2 generates a random number, generates a terminal key TK based on the generated random number, scrambles the terminal key TK and the 10 code of an IC card by a center key SK sent from a center 2 and registeres the scrambled contents in the center 2. At the time of transmitting the data of the IC card, the terminal 2 scrambles the data by its own key TK, transmits the scrambled data to the center 2 and the center 2 descrambles the data by its own key SK and registers the descrambled data or descrambles the data by the registered terminal key TK. Thereby the center 2 uses its own key SK and the terminal key TK of the communicating party which is generated based on an unfixed random number as decoding keys and decodes data received from the terminal equipment 2. |
