A 65 nm Cryptographic Processor for High Speed Pairing Computation

Pairings are attractive and competitive cryptographic primitives for establishing various novel and powerful information security schemes. This paper presents a flexible and high-performance processor for cryptographic pairings over pairing-friendly curves at high security levels. In this design, hardware for F_p2 arithmetic is optimized to accelerate the pairing computation, and especially a combined modular multiplier, which implements (AB + CD) based on Montgomery method, is proposed. This combined multiplier has the data path delay close to that of a single multiplier implementing (AB) but saves 20% area cost compared with two single multipliers. The Design I of the proposed processor is the first fabricated chip for pairing cryptography. An improved version, Design II, is implemented using TSMC 65-nm CMOS technology and achieves the working frequency of 633 MHz after placing and routing. As demonstrated, the optimal ate pairings of 126- and 128-bit security can be computed by Design II in 0.521 and 0.554 ms, respectively. These results outperform the hardware implementations reported by previous works.