Coarsely integrated operand scanning (CIOS) architecture for high-speed Montgomery modular multiplication

A generic coarsely integrated operand scanning (CIOS) architecture that provides high speed Montgomery modular multiplication is presented in This work. The architecture is capable of supporting varying operand sizes. It achieves a throughput of 210 Mbps, 289 Mbps and 334 Mbps for 128-bit, 256-bit and 512-bit operand sizes respectively, when implemented on a Virtex XC2 VP50 FPGA. Throughputs of up to 400 Mbps are achieved if the final subtraction in the Montgomery algorithm is excluded. To the authors´ knowledge this is the fastest Montgomery multiplication architecture reported in the literature.