Analysis of the Bit-Search Generator and Sequence Compression Techniques

  • Aline Gouget
  • Hervé Sibert
  • Côme Berbain
  • Nicolas Courtois
  • Blandine Debraize
  • Chris Mitchell
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3557)


Algebraic attacks on stream ciphers apply (at least theoretically) to all LFSR-based stream ciphers that are clocked in a simple and/or easily predictable way. One interesting approach to help resist such attacks is to add a component that de-synchronizes the output bits of the cipher from the clock of the LFSR. The Bit-search generator, recently proposed by Gouget and Sibert, is inspired by the so-called Self-Shrinking Generator which is known for its simplicity (conception and implementation-wise) linked with some interesting properties. In this paper, we introduce two modified versions of the BSG, called MBSG and ABSG, and some of their properties are studied. We apply a range of cryptanalytic techniques in order to compare the security of the BSGs.


Input Sequence Linear Complexity Information Rate Stream Cipher Output Sequence 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Aline Gouget
    • 1
  • Hervé Sibert
    • 1
  • Côme Berbain
    • 2
  • Nicolas Courtois
    • 3
  • Blandine Debraize
    • 3
    • 4
  • Chris Mitchell
    • 5
  1. 1.France Telecom Research and DevelopmentCaenFrance
  2. 2.France Telecom Research and DevelopmentIssy-les-MoulineauxFrance
  3. 3.Axalto Cryptographic Research & Advanced SecurityLouveciennes CedexFrance
  4. 4.Versailles UniversityVersaillesFrance
  5. 5.Information Security Group, Royal HollowayUniversity of LondonEghamUnited Kingdom

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