Sensor Network Security: Elliptic Curve Cryptography on SunSPOTs

Security is critical for wireless sensor networks. While several security mechanisms and protocols have been developed in the context of the Internet, many new challenges arise due to the characteristics of power-constrained wireless sensor networks. In this work, we focus on the Javaprogrammable SunSPOT device and elliptic curve cryptography (ECC). We present an analysis of run times and energy consumption. For our studies, we have developed our own implementation based on published pseudocode and Sun's BigInteger class. Our point multiplication on elliptic curves in prime finite fields is faster than that of Bouncy Castle, an open source ECC implementation. We investigate the impact of various parameters including key size, nonadjacent form, and prime versus binary fields. We believe such investigations to be an important step towards addressing the challenges of energy efficient security for Java-based sensor networks.