Analysis for Location-based Key Pre-distribution in Wireless Sensor Networks

Wireless sensor networks play key roles in many applications. They are often deployed in hostile environment where communications between sensor nodes must be encrypted. This requires the establishment of secure keys between the sensor nodes in the wireless sensor networks. As one of the methods establishing pairwise keys, location-based key pre-distribution scheme takes advantage of the observation that in static wireless sensor network, it is often possible to approximately determine the location of sensor nodes. In this paper, we evaluate the security and connectivity of location-based key pre-distribution scheme when a target field is partitioned using different methods. The analysis in this paper indicates that in the three possible partition methods, the hexagon-based scheme has the highest probability of establishing pairwise keys between sensor nodes, while the triangle-based key scheme can achieve the highest security. The tradeoff between connectivity and security should be taken into consideration in practice.