A method of enciphering information constituted by a finite sequence {S.sub.1,S.sub.2, . . . ,S.sub.N} of N symbols (S.sub.1,S.sub.2, . . . ,S.sub.N) selected from an alphabet A. There are defined both a secret convention of p key symbols K.sub.1, . . . ,K.sub.p selected form a second alphabet B, and a multivariate function M having m+1 variables (m<=N): M(X.sub.i1, . . . ,X.sub.im,Y) operating A.sup.m.quadrature.B in A, {i.sub.1, . . . ,i.sub.m} being m distinct indices in the range [1,N] and the function M being bijective relative to at least one (X.sub.i1) of the m variables of A. A succession of X permutations are performed on the sequences {S.sub.1,S.sub.2, . . . ,S.sub.N} such that where {S.sub.1,S.sub.2, . . . ,S.sub.N} is the sequence prior to the j.sup.th permutation, the sequence after the j.sup.th permutation is {S.sub.2,S.sub.3, . . . ,S.sub.N,Zj}, where Zj is equal to M(S.sub.i1, . . . ,S.sub.im,K.sub.j) the enciphered information being constituted by the sequence {S'.sub.1,S'.sub.2, . . . ,S'.sub.N} obtained after the X.sup.th permutation.