Implementation of key distribution schemes on real sensor network nodes
Hüseyin Ergin · Sabanci University · 2011
Wireless Sensor Network is a network type that consists of small sensor devices. The communication between these devices must be secured in case of an attack. Sensor devices have to share a secret key for secure communication. There are several key distribution schemes for wireless sensor networks in the literature. The most common key distribution scheme is the basic scheme which is proposed by Eschenauer and Gligor. Basic scheme has three phases; Key Predistribution, Shared Key Discovery and Path-key Establishment. Ergun proposed an alternative phase to Path-key Establishment, called Key Transfer phase. To the best of our knowledge, there is no real node implementation of the basic scheme. In this thesis, we implemented all three phases of the basic scheme and Ergun's Key Transfer phase on a real sensor device. We use TelosB devices, which have 10kB RAM, 1 MB ash memory, a microcontroller and RF interface. We design owcharts for each phase, create packet structures, implement in NesC programming language and test the implementation. We analyze the results using processing time, code space and memory usage metrics. We show that Key Transfer phase is more e cient than Path-key Establishment phase.