Correlation Via Linear Sequential Circuit Approximation of Combiners with Memory

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


Correlation properties of a general binary combiner with an arbitrary number of memory bits are analyzed. It is shown that there exists a pair of certain linear functions of the output and input, respectively, that produce correlated binary sequences. An efficient procedure, based on a linear sequential circuit approximation, is developed for finding such pairs of linear functions. The result may be a basis for a divide and conquer correlation attack on a stream cipher generator consisting of several linear feedback shift registers combined by a combiner with memory.


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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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