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Cryptanalysis of Sober-t32

  • Steve Babbage
  • Christophe De Cannière
  • Joseph Lano
  • Bart Preneel
  • Joos Vandewalle
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2887)

Abstract

Sober-t32 is a candidate stream cipher in the NESSIE competition. Some new attacks are presented in this paper. A Guess and Determine attack is mounted against Sober-t32 without the decimation of the key stream by the so-called stuttering phase. Also, two distinguishing attacks are mounted against full Sober-t32. These attacks are not practically feasible, but they are theoretically more efficient than exhaustive key search.

Keywords

NESSIE Cryptanalysis Security Evaluation Sober-t32 Guess and Determine Attack Distinguishing Attack 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Steve Babbage
    • 1
  • Christophe De Cannière
    • 2
  • Joseph Lano
    • 2
  • Bart Preneel
    • 2
  • Joos Vandewalle
    • 2
  1. 1.The CourtyardVodafone Group Research & DevelopmentNewbury, BerkshireUK
  2. 2.Dept. ESAT/SCD-COSICKatholieke Universiteit LeuvenHeverleeBelgium

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