Convergence of a Bayesian Iterative Error-Correction Procedure on a Noisy Shift Register Sequence

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 658)


Convergence of an algorithm for a linear feedback shift register initial state reconstruction using the noisy output sequence. based on a bitwise Bayesian iterative error-correction procedure and different weight parity-checks, is analyzed. It is proved that the self-composition of the Bayes error probability converges to zero if and only if the noise probability is less than a critical value expressed in terms of the numbers of parity-checks. An alternative approach to the critical noise estimation based on the residual error-rate after each iterative revision is also discussed.

Key words

Cryptanalysis Decoding Shift registers Fast correlation attack Algorithms Convergence 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  1. 1.Institute of Applied Mathematics and Electronics, Belgrade School of Electrical EngineeringUniversity of BelgradeBeogradYugoslavia

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