A Time-Memory Tradeoff Attack Against LILI-128

  • Markku-Juhani Olavi Saarinen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2365)


In this note we discuss a novel and simple time-memory tradeoff attack against the stream cipher LILI-128. The attack defeats the security advantage of having an irregular stepping function. The attack requires 246 bits of keystream, a lookup table of 245 89-bit words and computational effort which is roughly equivalent to 248 DES operations.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Markku-Juhani Olavi Saarinen
    • 1
  1. 1.Laboratory for Theoretical Computer ScienceHelsinki University of TechnologyHUTFinland

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