摘要 |
A data security system for protecting data discs and like bulk storage devices. A hardware encryption circuit (21) is incorporated in the disc controller (5) by which a host computer (3) accesses a disc (1). The encryption circuit (21) is activated (27) by a key, consisting of a card (25) and an associated number code, to decode data read from the disc or to encode data written to it. The system may thus be made automatic, without the intrusion of software security programs run by the host computer. Operation of the encryption circuit is wholly transparent to the host computer and no modification of the operating system or system software is necessary. Furthermore, the existing standard interfaces (7,9) of the disc controller with the disc and the computer can continue to be used. <IMAGE> |