Restoring connectivity in a resource constrained WSN

Wireless Sensor Networks (WSNs) in applications like battlefield surveillance or environmental monitoring are usually deployed in inhospitable environments, in which their constituent nodes are susceptible to an increased risk of failure due to hazardous operating conditions or adversary attacks. In these scenarios it is possible for multiple nodes to fail at the same time and partition the WSN into disjoint segments. Such loss of connectivity may cause service disruptions and render the WSN useless. Given the critical role a WSN plays and the fact that deployment of additional nodes may be infeasible, the WSN must have the ability to self-heal and restore connectivity by utilizing surviving resources. In this paper we present a distributed Resource Constrained Recovery (RCR) approach that reconnects a network partitioned into disjoint segments by strategically repositioning nodes to act as relays. In case the number of surviving relocatable nodes are insufficient to form a stable inter-segment topology, some of them are employed as mobile data collectors with optimized tours to reduce data latency. The performance of RCR is validated through mathematical analysis and simulation.