Markov Truncated Differential Cryptanalysis of Skipjack
UsingMarkov chains, we systematically compute all the truncated differentials of Skipjack, assuming the nonlinear G boxes are random permutations.We prove that an attacker with one random truncated differential from each of 2128 independently-keyed encryption oracles has advantage of less than 2-16 in distinguishing whether the oracles are random permutations or the Skipjack algorithm.
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