Connectivity Restoration in Wireless Sensor Networks Using Steiner Tree Approximations

Wireless sensor nodes are symbiotic when deployed in an activity region and heavily rely on each other for successful transmission of data. Therefore, failure of some nodes can possibly partition the network. Since these networks often operate unattended, nodes need to collectively maintain connectivity and resolve any reachability problem. Most published approaches for restoring connectivity are based on a single underlying principle of replacing the failed node without considering the possible fact that the location of the failed node could have been the reason for its failure. These approaches also tend to trigger a cascaded relocation of many nodes resulting in increased overhead. This paper presents a novel solution that pursues rearrangement of nodes while limiting the scope of the recovery to the vicinity of the failed node. The connectivity restoration is modeled as a variant of the Steiner tree formation problem and solved using novel heuristics. The proposed approach is validated through simulation.