WSN09-2: On the Performance of In-Situ Key Establishment Schemes for Wireless Sensor Networks

Due to its efficiency, symmetric key cryptography is very attractive in sensor networks. A number of key pre-distribution schemes have been proposed, but the scalability is often constrained by the unavailability of topology information before deployment and the limited storage budget within sensors. Recently, three in-situ key establishment schemes, SBK [13], LKE [14] and iPAK [15], have been proposed, which require no preloaded keying information but let sensors compute shared keys with their neighbors after deployment. We evaluate the three schemes through extensive simulation study and observe that they all have high scalability in network size. All of them can reach high connectivity in the key-sharing graph with low storage overhead. We also observe that SBK can fully satisfy the security requirements of large-scale sensor networks by simultaneously achieving good performance in terms of scalability, connectivity, storage overhead and resilience, while SBK outperforms LKE, LKE outperforms iPAK with respect to topology adaptability.