LOCK: an historical perspective

LOCK is an advanced development of hardware-based computer security and crypto-graphic service modules. Much of the design and some of the implementation specifications are complete. The Formal Top Level Specification (FTLS) also is complete and the advanced noninterference proofs are beginning. This hardware-based approach has brought the LOCK project into many uncharted areas in the design, verification, and evaluation of an integrated information security system. System integration promises to be the single largest programmatic problem. Our verification tools seem able to verify design only and not implementation.