Method for testing the intactness of stored data in a processing facility for sheet material such as bank notes or papers of value

US5870469A · kind A · utility

Assignee

• GIESECKE & DEVRIENT GMBH · DE

Inventors

• Bodo Albert · Hersbruck, DE
• Wilhelm Buntscheck · Wolfratshausen, DE

Key dates

• Filing date: Feb 13, 1997
• Grant date: Feb 9, 1999
• Expiry date: Feb 13, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G06F21/602
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

For testing the intactness of stored data, intact data corresponding to the data to be tested from a component of the processing facility in a certain operating state of the processing facility in the intact state are first stored in a test device. To check the intactness of the data to be tested in a component a key is produced in the test device for each test, said key being different from those of prior tests. Using this key and a cryptographic algorithm one prepares two cryptograms. One cryptogram is prepared from the data to be tested by the component of the processing facility in which the data to be tested are stored. The other cryptogram is prepared from the intact data by the test device. After that the two cryptograms are compared with each other. If the cryptograms match, the data to be tested match the intact data and thus have no undesirable changes.