On the security of recharging social security cards

The internal structure of IC cards is composed of CUP, ROM, RAM, EEPROM and I/O, and constructs a complete computer security system. Users’ data is placed in the EEPROM protected by the logic encryption; the COS mask is in the ROM and the RAM stores the intermediate variable when COS is running. For instance, users’ process keys are placed in the RAM when they are formed, and if the system loses power, it would lose the keys automatically, thus ensuring the security of users’ keys.