23.01.2012 Lecturer: Samed Bajrić

Title: Almost Perfect Nonlinear functions

Abstract: In this talk we present some basic properties of Almost Perfect Nonlinear (APN) functions over finite field of characteristic 2 and investigate some open problems. We provide the characterizations of Almost Perfect Nonlinear functions and of APN permutations by means of their component functions, which can be used in an iterated secret-key block cipher as a round function to protect it from a differential cryptanalysis. We conclude with the list of all, up to equivalence, APN and Almost Bent (AB) functions, which are equivalent to certain power functions f: GF(2^n) –> GF(2^n), f(x) = x^k.

DOWNLOAD THE SLIDES FROM THE TALK: DOWNLOAD!