How to Strengthen Pseudo-random Generators by Using Compression

  • Aline Gouget
  • Hervé Sibert
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4004)


Sequence compression is one of the most promising tools for strengthening pseudo-random generators used in stream ciphers. Indeed, adding compression components can thwart algebraic attacks aimed at LFSR-based stream ciphers. Among such components are the Shrinking Generator and the Self-Shrinking Generator, as well as recent variations on Bit-Search-based decimation. We propose a general model for compression used to strengthen pseudo-random sequences. We show that there is a unique (up to length-preserving permutations) construction that reaches an optimal trade-off between output rate and security against several attacks.


Input Sequence Output Rate Stream Cipher Output Sequence Compression Function 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Aline Gouget
    • 1
  • Hervé Sibert
    • 1
  1. 1.France Telecom Research and DevelopmentCaenFrance

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