OnAlmostPerfect Nonlinear Functions

differential andlinear cryptanalysis, EUROCRYPT'94, LNCS950,pp.356-365, 1995. A function FF:-FF;isalmost perfect nonlinear[4]K. Nyberg. Differentially uniform mappings for cryptography, EUROCRYPT'93, LNCS 765,pp.55-64, (APN)if, foreverya.0, b inF;,theequation F(x)±1994. F(x+a)=b hasatmosttwosolutions [4]. Whenusedasan S-boxina blockcipher, itopposes thenanoptimum Biography: resistance todifferential cryptanalysis. Thefunction F is almost bent(AB)iftheminimumHamming distance