Patent ID: 8798263
Filing Date: 2014-08-05
Classification: H04L

Abstract:
1. A method for encrypting digital data, said data being divided into a sequence of N first blocks of a same length of n bits each, N being an integer greater than 1, n being an integer greater than 1, comprising steps of: inputting the sequence of N first blocks into a pre-processing module comprising a processor, registers, an arithmetic module, and a memory containing a set including N invertible elements, the N first blocks and the N invertible elements being within a predetermined finite ring, the arithmetic module including multiplier modules, addition modules and inverter modules, and using the arithmetic module to determine N resulting blocks based on the N first blocks and the N invertible elements by executing resulting block determination operations including, outputting a sequence of the N resulting blocks, each of the N resulting blocks having a length identical to a corresponding block of the input sequence of N first blocks, and ciphering each of the sequence of the N resulting blocks, by a ciphering module, with a block cipher in a chaining mode from the first block of the sequence of the N resulting blocks to the last block of the sequence of the N resulting blocks with a ciphering algorithm to produce a sequence of N encrypted blocks, said encrypted blocks having each a same length.