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:
Feb. 19, 2008
Filed:
Feb. 14, 2002
Louis Goubin, Paris, FR;
Louis Goubin, Paris, FR;
Axalto, S.A., Montrouge, FR;
Abstract
The invention relates to security for computer systems and a method for protecting computer systems, particularly those employing an encryption for the protection of sensitive information. A cryptographic algorithm is implemented in the protected system using Boolean operations and arithmetic operations wherein at least one variable is separated into several parts, in a Boolean separation using a Boolean operation, and in an arithmetic separation using an arithmetic operation. In order to switch from one of the operations to the other, a predetermined number of Boolean and arithmetic operations is performed on the parts and at least one random number, so that for each of the values appearing during the operation, there is no correlation with the variable.