Linear Filtering of Nonlinear Shift-Register Sequences

  • Berndt M. Gammel
  • Rainer Göttfert
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3969)


Nonlinear n-stage feedback shift-register sequences over the finite field \(\mathbb{F}_q\) of period q n –1 are investigated under linear operations on sequences. We prove that all members of an easily described class of linear combinations of shifted versions of these sequences possess useful properties for cryptographic applications: large periods, large linear complexities and good distribution properties. They typically also have good maximum order complexity values as has been observed experimentally. A running key generator is introduced based on certain nonlinear feedback shift registers with modifiable linear feedforward output functions.


Linear Complexity Stream Cipher Periodic Sequence Irreducible Polynomial Linear Filter 
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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© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Berndt M. Gammel
    • 1
  • Rainer Göttfert
    • 1
  1. 1.Infineon Technologies AGMunichGermany

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