METHOD FOR CRYPTOGRAPHIC CONVERSION OF L-BIT DIGITAL-DATA INPUT BLOCKS INTO L-BIT OUTPUT BLOCKS Russian patent published in 2002 - IPC

FIELD: electric communications and computer engineering; cryptographic methods and devices for data encryption. SUBSTANCE: method involves division of data block into N≥2 subblocks, generation of at least one binary vector with respect to subblock value at each step, and transformation of subblock depending on binary vector structure; during next step of subblock conversion binary vector is generated depending on binary vector structure at subblock conversion preceding step. In addition subblock is altered by subjecting it to cyclic shift by number of bits equal to current value of binary vector; subblock is also transformed by way of substitution operation corresponding to substitution V-table. EFFECT: enhanced encryption stability in data block conversion and encryption conversion speed. 3 cl, 3 dwg