A new RSA cryptosystem hardware design based on Montgomery's algorithm

In this paper, we propose a new algorithm based on Montgomery's algorithm to calculate modular multiplication that is the core arithmetic operation in an RSA cryptosystem. The modified algorithm eliminates over large residue and has very short critical path delay that yields a very high speed processing. The new architecture based on this modified algorithm takes about 1.5n/sup 2/ clock cycles on the average to finish one n-bit RSA operation. We have implemented a 512-bit single-chip RSA processor based on the modified algorithm with Compass 0.6-/spl mu/m SPDM CMOS cell library. The simulation results show that the processor can operate up to 125 MHz and deliver the baud rate of 164 Kbits/s on the average.