Patent ID: 8891758
Filing Date: 2014-11-18
Classification: H04L

Abstract:
1. A block encryption device comprising: an input unit configured to divide input data into a k-number of blocks; a Feistel permutation unit for an R-number of rounds, the Feistel permutation unit configured to perform Feistel permutation, with two blocks as a set, using an encryption key generated from one round to another; a block permutation unit configured to perform block permutation equivalent to a binary de Bruijn graph with symmetric type 2 branch coloring, having a 2t-number, equal to one-half the number of division k, of nodes, where t>2, the de Bruijn graph indicating a transitioning from an even-numbered block to an odd-numbered block with an arrow line of a first color and indicating a transitioning from an odd-numbered block to an even-numbered block with an arrow line of a second color, using the following functions: that decide on the colors of the arrow lines from a node u represented by a t-bit sequence (u1, u2, . . . , ut) to a node v represented by another t-bit sequence (v1, v2, . . . , vt); and an output unit configured to concatenate the as-permuted k-number of blocks to output the concatenated blocks.