METHOD FOR ENCRYPTING OF BINARY DATA UNITS Russian patent published in 1999 - IPC

FIELD: communication and computer engineering. SUBSTANCE: method involves splitting data units into V sub-units, sequential encrypting of sub-units, which are subjected to at least one operation of encrypting, which depends on values of input unit. Goal of invention is achieved by using sub-unit bit transposition as operation of encrypting, and by using additional sub-unit bit transposition operation depending on secret key. In addition method involves additional generation of binary vector V, so that sub-unit bit transposition operation depends on value of V. Said binary vector during current converting step depends on its value at previous converting step and value of one of sub-units. EFFECT: increased number of possibilities for operation which depends on unit under encrypting, increased protection against differential and linear cryptographic analysis. 2 cl, 5 dwg