Nodes are designed to be small, cheap and lightweight and
thus have limited computing capacity and batteries. This poses
a problem because the traditional cryptographic solutions that
work for PCs and workstations are infeasible on these lowpower
sensor nodes [1]. The utility of wireless sensor networks
sees them being deployed in dangerous or inaccessible areas
and this adds to the complexity of securing the network since it
is usually out of the physical reach of the operator. Adversaries
therefore have the advantage of being able to steal nodes
and reverse-engineer them to obtain cryptographic keys or
other sensitive information. More worrying is the fact that