| 摘要 |
PROBLEM TO BE SOLVED: To highly reliably confirm whether a communicating party is an intended true party or not by letting a 1st system discriminate a system, which is the transmission source of worked cryptographic information, as a 2nd system when both the worked cryptographic information generated at the 1st and 2nd systems while using the same working information satisfy the conditions of coincidence. SOLUTION: When digit designation information shows 2nd to 4th digits from the left and a medium password number is 1234567890ABCDEFG, for example, on the side of a client, '234' is generated as a selected password number. When a communication unit 203 receives the selected password number or the like on the client side, on the side of a bank, the received client password number and the selected password number are checked. It is discriminated while referring to a client managing file whether the client password number and a settled account number are correspondent or not. Further, based on the digit designation information, the selected password number such as '234', for example, is generated from the medium password number registered corresponding to the client password number and it is checked whether this number is coincident with the selected password number received from the client side or not. |
