A Fast Window-based Scalar Multiplication Algorithm for Elliptic Curve Cryptography in Wireless Sensor Networks

Abstract

In recent years, the security of wireless sensor networks (WSNs) has become more and more important due to extensive applications of WSNs in the areas of military, environmental monitoring, health and homecare. Cryptography is a basic technique to provide security services for WSNs. Owing to the limitation of resources in sensor nodes, the computation, communication, and memory overheads introduced by performing cryptography must be minimized. Elliptic curve cryptography (ECC) compared to other cryptosystems requires less communication, computation, and memory usages. Hence, ECC is suitable for wireless sensor network security because ECC only requires 160 bits length of keys to achieve the same level of security as RSA using 1024 bits length of keys. However, the key generations in ECC, which involve with a large number of scalar multiplications, is still time consuming when applied to sensor nodes. In this paper, we propose an enhanced window-based mutual opposite form (EW-MOF) for scalar multiplication with ECC in WSNs. The proposed EW-MOF combines MOF with an enhanced window method that can reduce not only pre-computation time and memory usage, but also average key generation time including pre-computation time in each sensor node. Our analysis has shown that the proposed