Method for the implementation of Montgomery modular reduction

摘要

Two double-entry multiplexers (41,42) supply shift registers (10,12) and allow entry of a modulo (N) and initiating bits (O). A subtracting circuit (27) has one input connected to the output of one register (10) and the other connected to the output of a multiplexer (36). The multiplexer (36) has one input connected to earth and the other to the output of the second shift register (12). The inputs are selected by a signal (SC) from a circuit (44) which stores comparisons and is supplied from a subtraction unit (40) and gate (43).