Low latency FPGA implementation of twisted Edward curve cryptography hardware accelerator over prime field

Abstract

The performance of any elliptic curve cryptography hardware accelerator significantly relies on the efficiency of the underlying point multiplication (PM) architecture. This article presents a hardware implementation of field-programmable gate array (FPGA) based modular arithmetic, group operation, and point multiplication unit on the twisted Edwards curve (Edwards25519) over the 256-bit prime field. An original hardware architecture of a unified point operation module in projective coordinates that executes point addition and point doubling within a single module has been developed, taking only 646 clock cycles and ensuring a better security level than conventional approaches. The proposed point multiplication module consumes 1.4 ms time, operating at a maximal clock frequency of 117.8 MHz utilising 164,730 clock cycles having 183.38 kbps throughput on the Xilinx Virtex-5 FPGA platform for 256-bit length of key. The comparative assessment of latency and throughput across various related recent works indicates the effectiveness of our proposed PM architecture. Finally, this high throughput and low latency PM architecture will be a good candidate for rapid data encryption in high-speed wireless communication networks.