Generic Attacks and the Security of Quartz

  title={Generic Attacks and the Security of Quartz},
  author={Nicolas T. Courtois},
  booktitle={Public Key Cryptography},
  • N. Courtois
  • Published in Public Key Cryptography 6 January 2003
  • Computer Science, Mathematics
The signature scheme Quartz is based on a trapdoor function G belonging to a family called HFEv-. It has two independent security parameters, and we claim that if d is big enough, no better method to compute an inverse of G than the exhaustive search is known. Such a (quite strong) assumption, allows to view Quartz as a general construction, that transforms a trapdoor function into a short signature scheme. The main object of this paper is the concrete security of this construction. On one hand… 

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