Method and system for obfuscating a cryptographic function

i i ii i o11o1 c111jEmbodiments include a system, wherein a server provides a cryptographic function F to an execution device in an obfuscated form. The function F composes output of a plurality of the mapping tables T(0≦i≦n; n≧1) using an Abelian group operator. A processor chooses tables O and C such that C[x] O[x]=0, x Dand creates tables T′, 0≦i≦m; n≦m≦n+1, where for 0≦i≦n, each Table T′represents the respective corresponding table Tand at least one table T′, 0≦o≦n, being formed through an Abelian composition of Tand O, and at least one table T′, 0≦c≦m, c≠o; being formed through an Abelian composition that includes C.