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:
Oct. 13, 2009
Filed:
Sep. 07, 1999
Harald Vater, Giessen, DE;
Hermann Drexler, Munich, DE;
Harald Vater, Giessen, DE;
Hermann Drexler, Munich, DE;
Giesecke & Devrient GmbH, Munich, DE;
Abstract
The invention relates to a data carrier having a semiconductor chip () with at least one memory. The memory contains an operating program that is able to perform at least one operation (h). In order to prevent unauthorized access to the data (x) processed with the operation (h), both said data and the operation (h) itself are disguised. The disguising of the data (x) and the operation (h) is coordinated such that the disguised operation (h, h) generates either the output data (y) of the undisguised operation (h) or disguised output data (y{circle around (x)}R) from which the output data (y) can be determined.