Cryptanalysis of IDEA-X/2

  • Håvard Raddum
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2887)


IDEA is a 64-bit block cipher with a 128-bit key designed by J. Massey and X. Lai. At FSE 2002 a slightly modified version called IDEA-X was attacked using multiplicative differentials. In this paper we present a less modified version of IDEA we call IDEA-X/2, and an attack on this cipher. This attack also works on IDEA-X, and improves on the attack presented at FSE 2002.


Cryptography block ciphers differential cryptanalysis IDEA 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Håvard Raddum
    • 1
  1. 1.Dep. of InformaticsThe University of BergenNorway

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