Tight Indistinguishability Bounds for the XOR of Independent Random Permutations by Fourier Analysis

ePrint Report: Tight Indistinguishability Bounds for the XOR of Independent Random Permutations by Fourier Analysis

Itai Dinur

The XOR of two independent permutations (XoP) is a well-known construction for achieving security beyond the birthday bound when implementing a pseudorandom function using a block cipher (i.e., a pseudorandom permutation). The idealized construction (where the permutations are uniformly chosen and independent) and its variants have been extensively analyzed over nearly 25 years.


The best-known information-theoretic indistinguishability bound for the XoP construction (due …

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