  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.
