Improving the Randomized Initial Point Countermeasure Against DPA

DPA-countermeasures are one of the essential technology for implementing elliptic curve cryptosystems (ECC) on smart cards. Not only standard DPA but also recently proposed refined power analysis (RPA) and zero value analysis (ZVA) should be considered. Itoh, Izu and Takenaka proposed a secure and efficient countermeasure (the randomized initial point countermeasure, RIP) in order to resist these attacks. Then, Mamiya, Miyaji and Morimoto improved the efficiency. This paper also aims at improving RIP in another direction. As a result, compared to the original RIP, about 28% improvement can be established. In other words, the proposed countermeasure has almost no penalty from a non DPA-resistant scalar multiplication.