EA and CCZ Equivalence of Functions over GF(2n)
نویسنده
چکیده
EA-equivalence classes and the more general CCZ-equivalence classes of functions over GF (2) each preserve APN and AB properties desirable for S-box functions. We show that they can be related to subsets c[T ] and g[T ] of equivalence classes [T ] of transversals, respectively, thus clarifying their relationship and providing a new approach to their study. We derive a formula which characterises when two CCZ-equivalent functions are EA-inequivalent.
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