PERMUTATION CIPHER SCHEME USING POLYNOMIALS OVER A FIELD

A permutation cipher scheme using polynomials over a field is presente d. A permutation as well as substitution plays a major role in almost all conventional cryptosystems. But the security of the permutation de pends on how symbols are permuted. This paper proposes the use of poly nomials for the permutation and show that the scheme satisfies the fol lowing security criteria. (1) There are enough encryption keys to defe nd exhaustive attacks. (2) The permutation moves almost all samples in to places which are different from the original places. (3) Most sampl es are shifted differently by different permutations. The permutation cipher scheme could be regarded as a scheme based on Reed-Solomon code s. The information symbols of the codes compose a key of the permutati on cipher scheme.