| 摘要 |
PURPOSE:To effectively prevent forgery or dead copy of information recorded in a magnetic or optical recording part with respect to the hybrid card provided with an IC part and the magnetic or optical recording part. CONSTITUTION:An authenticator (MAC) calculated by using a prescribed unidirectional function for recorded data in a magnetic recording part 5 and an optical recording part 7 is stored in an EEPTOM in an IC part 3. Each time new data is written in the magnetic recording part 5 and the optical recording part 7, MAC is calculated again to update MAC in the EEPROM. This update of MAC is executed only when prescribed authenticating procedures are cleared; but if an illegal rewriter or the like is used to illegally forge the data in recording parts 5 and 7, MAC is not updated because they are not cleared. When this card 1 is used in the transaction processing system, data are read out from recording parts 5 and 7 to calculate MAC, and this calculated MAC is collated with MAC in the EEPROM, and the user of the card is permitted only when they coincide with each other. |
