The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 17, 1993
Filed:
Sep. 21, 1992
Applicant:
Inventors:
Dennis G Abraham, Concord, NC (US);
Steven G Aden, Cedar Park, TX (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04L / ; G06F / ;
U.S. Cl.
CPC ...
380 49 ; 380 50 ; 395425 ;
Abstract
The microprocessor resides along with its protected real address space in a secure module surrounded by tamper resistant circuitry pad. Encryption programs and encryption keys are stored in the protected memory. A second real address space is also connected to the address and data bus of the microprocessor in order to provide program and data space for a user. Gating circuitry prevent the exposure of instructions and data form the privileged memory from appearing outside of the secure module. The gating circuits switch address spaces by recognizing a sequence of predetermined addresses.