The Design of a Stream Cipher LEX

  • Alex Biryukov
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4356)


In this paper we define a notion of leak extraction from a block cipher. We demonstrate this new concept on an example of AES. A result is LEX: a simple AES-based stream cipher which is at least 2.5 times faster than AES both in software and in hardware.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Alex Biryukov
    • 1
  1. 1.University of Luxembourg, FDEF, Campus Limpertsberg, 162 A, Avenue de la Faiencerie, L-1511 LuxembourgLuxembourg

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