Abstract: An apparatus for permitting access to protected code, protected data or protected devices only when a computer system is in a trusted state, where said trusted state occurs only when said system is executing trusted code under a set of preselected conditions. This apparatus also has a device for exiting the trusted state and for preventing access to protected code, data and devices when the trusted state is exited. The computer system is also programmed to automatically generate a disabling signal upon the completion of execution of trusted code, and this disabling signal will result in the prevention of access to protected devices or code.
Type:
Grant
Filed:
September 2, 1997
Date of Patent:
October 16, 2001
Assignee:
International Business Mcahines Corporation
Inventors:
Mario Bizzaro, Vincenzo Condorelli, Michel Henri Theodore Hack, Jeffrey Kenneth Kravitz, Mark John Lindemann, Elaine Rivette Palmer, Gianluca Pedrina, Sean William Smith, Steve Harris Weingart