Showing papers on "MDS matrix published in 2000"

Device and method for deciding parameter, ciphering device, and deciphering device

Abstract: PROBLEM TO BE SOLVED: To solve the problem that an S-box and an MDS matrices comprised in a ciphering device as the system components offset their effects against each other in spite of the X-box and the MDS intended to realize optimal complexity according to the design policies independent of each other, therefore, the ciphering device has had a probability of being rather unsafe. SOLUTION: By evaluating complexity of a result of multiplication of each candidate of MDS matrix elements by the matrix elements of a given S-box; evaluating, based on a evaluation result of this complexity, the complexity of the combinations of the matrix element candidates composing the MDS matrix; further, evaluating similar complexity also of an inverse matrix to this MDS matrix; and based on the evaluation results of the complexity of these matrices, a method for determining an MDS matrix giving the optimal complexity in the combination with the S-box, and a ciphering device adopting the MDS matrix obtained by the method are provided.