Patent ID: 7352860
Filing Date: 2008-04-01
Classification: H04L

Abstract:
1. A method of enciphering information constituted by a finite sequence {S 1 ,S 2 , . . . ,S N } of N symbols {S 1 ,S 2 , . . . ,S N } selected from an alphabet A, wherein there are defined both a secret convention (K) of p key symbols K 1 , . . . ,K p selected from a second alphabet B, and a multivariate function M having m+1 variables (m<=N): M(X i1 , . . . ,X im ,Y) operating A m ×B in A, {i 1 , . . . , i m } being m distinct indices in the range [1 ,N] and the function M being bijective relative to at least one (X i1 ) of the m variables of A, said enciphering method comprising: initially placing the N symbols S performing a succession of X turns of the shift register implementing a succession of X permutations on the sequences {S wherein the number X of permutations is greater than several times the length N of the sequences {S wherein the number m is equal to 3, the function M being defined by M(X wherein the function M(X t 1 and t 2 being the functions associated with two Latin squares T 1 and T 2 of size equal to the number N.