Combined attacks on block ciphers

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2009

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Öztop, Neşe

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Cryptanalytic methods are very important tools in terms of evaluating the security of block ciphers in a more accurate and reliable way. Differential and linear attacks have been the most effective cryptanalysis methods since the early 1990s. However, as the technology developed and more secure ciphers are designed, these fundamental methods started to be not so efficient. In order to analyze the ciphers, new methods should be introduced. One approach is inventing new techniques that are different from the existing ones. Another approach is extending or combining known cryptanalytic methods to analyze the cipher in a different way. This thesis is a survey of the attacks that are generated by combination of existing techniques and their applications on specific block ciphers. Mentioned attacks are namely differential-linear, differential-bilinear, higher order differential-linear, differential-nonlinear, square-nonlinear, impossible differential and boomerang type attacks.

Subject Keywords

Cryptography.

URI

http://etd.lib.metu.edu.tr/upload/2/12610875/index.pdf
https://hdl.handle.net/11511/18605

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Graduate School of Applied Mathematics, Thesis

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Citation Formats

N. Öztop, “Combined attacks on block ciphers,” M.S. - Master of Science, Middle East Technical University, 2009.