Patent · US Expired

Leak-resistant cryptographic method and apparatus

US6304658A · kind A · utility

139Cited by
10References
54Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 31, 1998
Grant dateOct 16, 2001
Priority date
Expiry dateDec 31, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2209/56
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

The present invention provides a method and apparatus for securing cryptographic devices against attacks involving external monitoring and analysis. A "self-healing" property is introduced, enabling security to be continually re-established following partial compromises. In addition to producing useful cryptographic results, a typical leak-resistant cryptographic operation modifies or updates secret key material in a manner designed to render useless any information about the secrets that may have previously leaked from the system. Exemplary leak-proof and leak-resistant implementations of the invention are shown for symmetric authentication, certified Diffie-Hellman (when either one or both users have certificates), RSA, ElGamal public key decryption, ElGamal digital signing, and the Digital Signature Algorithm.

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