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Further Observations on the Structure of the AES Algorithm

  • Beomsik Song
  • Jennifer Seberry
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2887)

Abstract

We present our further observations on the structure of the AES algorithm relating to the cyclic properties of the functions used in this cipher. We note that the maximal period of the linear layer of the AES algorithm is short, as previously observed by S. Murphy and M.J.B. Robshaw. However, we also note that when the non-linear and the linear layer are combined, the maximal period is dramatically increased not to allow algebraic clues for its cryptanalysis. At the end of this paper we describe the impact of our observations on the security of the AES algorithm. We conclude that although the AES algorithm consists of simple functions, this cipher is much more complicated than might have been expected.

Keywords

Cyclic Properties SubBytes transformation ShiftRows transformation MixColumns transformation Maximal period 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Beomsik Song
    • 1
  • Jennifer Seberry
    • 1
  1. 1.Centre for Computer Security Research, School of Information Technology and Computer ScienceUniversity of WollongongWollongongAustralia

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