10-Round Feistel is Indifferentiable from an Ideal Cipher

نویسندگان

  • Dana Dachman-Soled
  • Jonathan Katz
  • Aishwarya Thiruvengadam
چکیده

We revisit the question of constructing an ideal cipher from a random oracle. Coron et al. (Journal of Cryptology, 2014) proved that a 14-round Feistel network using random, independent, keyed round functions is indifferentiable from an ideal cipher, thus demonstrating the feasibility of such a construction. Left unresolved is the best possible efficiency of the transformation. We improve upon the result of Coron et al. and show that 10 rounds suffice.

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عنوان ژورنال:
  • IACR Cryptology ePrint Archive

دوره 2015  شماره 

صفحات  -

تاریخ انتشار 2015