An Improved Attack on the Shrinking Generator
نویسندگان
چکیده
This work proposes a known-plaintext attack on the Shrinking Generator through its characterization by means of Cellular Automata. It is based on the computation of the characteristic polynomials of sub-automata and on the generation of the Galois field associated to one of the Linear Feedback Shift Registers components of the generator. The proposed algorithm allows predicting a large number of unseen bits of the keystream sequence, thanks to the knowledge of both registers lengths, the characteristic polynomial of one of the registers, and some keystream bits. Key-Words: Cellular automata, cryptanalysis, stream cipher, shrinking generator
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