MODULAR MULTIPLICATION METHOD AND SMART CARD USING THE METHOD

摘要

A modular multiplication method and a smart card performing the same are provided to perform multiplication computation of data of predetermined bits in a modular multiplier on the basis of Montgomery algorithm, thereby accelerating modular computation and improving processing rate of generation and verification of digital signature and coding/decoding. A modular multiplication method and a smart card performing the same comprise the following steps of: receiving modulus N of multiple k bits through a modular register(S201); receiving first data through a first operand register and second data through a second operand register(S203,S205); performing a first modular computation(S207); storing a value computed by a central processing unit on the basis of the k bits in the first operand register(S209); storing the first modular computation in the second operand register(S211); and outputting the computation results corresponding to the first and second data(S215).