Deciding Irreducibility/Indecomposability of Feedback Shift Registers is NP-hard

Lin Wang

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arXiv · 1702.01423

Deciding Irreducibility/Indecomposability of Feedback Shift Registers is NP-hard

Lin Wang

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Abstract

Feedback shift registers(FSRs) are a fundamental component in electronics and secure communication. An FSR $f$ is said to be reducible if all the output sequences of another FSR $g$ can also be generated by $f$ and the FSR $g$ has less memory than $f$. An FSR is said to be decomposable if it has the same set of output sequences as a cascade connection of two FSRs. It is proved that deciding whether FSRs are irreducible/indecomposable is NP-hard.

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Lin Wang. 2017-02-05. Deciding Irreducibility/Indecomposability of Feedback Shift Registers is NP-hard. https://arxiv.org/abs/1702.01423

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