Patent · US Expired

Apparatus and method for modifying microprocessor system at random and maintaining equivalent functionality in spite of modification, and the same microprocessor system

US6526511B1 · kind B1 · utility

5Cited by
5References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 1998
Grant dateFeb 25, 2003
Priority date
Expiry dateDec 23, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F21/77
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

The present invention discloses a method for randomizing a microprocessor system, such as an IC card, in order to prevent the microprocessor system from being tampered with. The method ensures that the randomized microprocessor system realizes a functionality equivalent to that of an original microprocessor system and enables easy modification of a configuration of the microprocessor system. In the context of this disclosure, to randomize a microprocessor system means to randomize a microprocessor and a program included in the microprocessor system while maintaining an equivalence of functionality realized by the microprocessor system regardless of this randomization. According to the present invention, the method for randomizing a microprocessor system performing a given functionality consists in (a) randomizing items stored in a memory in accordance with randomizing information, and (b) randomizing a microprocessor so as to allow the microprocessor to have an access to the randomized items stored in the memory. Thus, a randomized microprocessor system performing a functionality equivalent to the given functionality is generated.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.