Dual-domain Scalable Elliptic Curve Cryptography Processor Key Technologies

With the rapid development of computer technology and Internet, information security is given more and more attention.Cryptology which is the key technology of information security can be divided into three categorise: stream cipher, symmetrical cipher (private-key cipher) and asymmetrical cipher (public-key cipher). Among the three, public-key cryptography is very important in the security applications such as key-exchange, signature and authentication.Currently, the two main crypto systems are RSA (based on IF problem) and ECC (based on Elliptic Curve Discrete problem). Elliptic curve cryptography (ECC) has more attractive attributes when compared to RSA: short key length for same security level; higher operation speed; occupy less memory and network bandwidth. So ECC is more suitable for those constrained application such as smart card and wireless applications.This thesis focuses on the key technology of low-cost high-performance dual-field scalable ECC processor: Until now, the unified national standard of elliptic curve cryptography is not available.Due to this reason, various types of elliptic curve cryptosystem exists, some are based on prime field while the others based on binary field.So a dual-field ECC processor will be compatible with existing systems.Scalable design does well in the trade-off between cost and performance, the maximum operand size which the design can handle is decided by the memory depth, not like ordinary design which is decided by the datapath.So a scalable design can handle the increasing security demand. As the most important operation in ECC, the various point multiplication algorithms are studied and analyzed.And the Montgomery Ladder method which have excellent parallelism is adopted for binary field, and NAF method combined with On-the-fly algorithm is adopted for prime field.The the implementation aspect, this thesis proposed a 32-bit width dual-field scalable Montgomery modular multiplier(squarer) which supports dual-field modular multiplication(square), dual-field addtion and subtraction and etc.Its datapath is based on a optimize Wallace tree, suitable for high efficiency high-radix multi-precision algorithm.