Public Key Identification Based on the Equivalence of Quadratic Forms

  • Rupert J. Hartung
  • Claus-Peter Schnorr
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4708)

Abstract

The computational equivalence problem for quadratic forms is shown to be NP-hard under randomized reductions, in particular for indefinite, ternary quadratic forms with integer coefficients. This result is conditional on a variant of the Cohen-Lenstra heuristics on class numbers. Our identification scheme proves knowledge of an equivalence transform.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Rupert J. Hartung
    • 1
  • Claus-Peter Schnorr
    • 1
  1. 1.Johann Wolfgang Goethe Universität Frankfurt a. M., Postfach 11 19 32; Fach 238, 60054 Frankfurt a. M.Germany

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