F-FCSR Stream Ciphers

  • François Arnault
  • Thierry Berger
  • Cédric Lauradoux
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4986)


Feedback with Carry Shift Registers (FCSRs) are a promising alternative to Linear Feedback Shift Registers (LFSRs) for the design of stream ciphers. The main difference between these two automata lies in the computation of the feedback. While LFSRs use simple bitwise addition, FCSRs use addition with carries. Hence, the transition function of an FCSR is non-linear, more precisely quadratic. Since FCSRs were introduced by Goresky and Klapper [11], the properties of the sequences generated by an FCSR are now considered well mastered from a mathematical point of view.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • François Arnault
    • 1
  • Thierry Berger
    • 1
  • Cédric Lauradoux
    • 2
  1. 1.XLIM DMIUniversité de LimogesFrance
  2. 2.INRIA RocquencourtFrance

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