Scalable Link-Layer Key Agreement in Sensor Networks

Link layer key agreement between neighboring nodes is a fundamental issue for securing sensor networks deployed in unattended and hostile environments. Recent research often assumed a pre-distributing approach so that each pair of neighboring nodes agrees on a shared key directly or indirectly through a multi-hop path. The shortcomings include large memory cost, poor resilience against node compromise, low secure connectivity, etc. In this paper, we present a link-layer key agreement scheme combining a scalable key agreement model and space diversity. In contrast to previous proposals, our scheme have higher resilience to node compromise attacks with much smaller memory costs and high secure connectivity so that much less energy needs to be consumed in establishing indirect keys through multi-hop routing.