Cross Layer Implementation of Key Establishment and Configuration Protocols in WSN

Security in Wireless Sensor Networks (WSN) can be achieved by establishing shared keys among the neighbor sensor nodes to create secure communication links. The protocol to be used for such a pairwise key establishment is a key factor determining the energy to be consumed by each sensor node during the secure network configuration. On the other hand, to achieve the optimum network configuration, nodes may not need to establish pairwise keys with all of their neighbors. Because, links to be established are defined by the network configuration protocol and as long as the network connectivity requirements are satisfied, number of links to be secured can be limited accordingly. In this sense, key establishment and network configuration performances are related to each other and this cross relation should be taken into consideration while implementing security for WSN. In this paper, we have investigated the cross layer relations and performance figures of the selected randomized pre-distribution and public key based key establishment protocols with the configuration protocol we proposed in a separate publication. Simulation results indicate that total network configuration energy cost can be reduced by reducing the number of links to be secured without affecting the global network connectivity performance. Results also show that the energy and resilience performances of the public key establishment can be better than the key pre-distribution for a given set of network configuration parameters.