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. 31, 1999
Filed:
Feb. 18, 1997
Paul Thomas Kitaj, Gilbert, AZ (US);
Douglas Allen Hardy, Scottsdale, AZ (US);
Mark Richard Enstone, Scottsdale, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A device driver (104) is used to provide a fail-safe interface between a plurality of client applications and a cryptographic card. Device driver (104) ensures separation between red data, black data, and command data. Device driver (104) uses objects and object handles to control data flow. Device driver (104) uses several simplex channels to control data flow. Each channel is managed separately using its own object, and each channel has unique access protection through the object handles. Within device driver (104), the simplex channel interfaces are kept separate and functional separation of the data and command memory is maintained to provide fail-safe data isolation.