Topology Management Techniques for Tolerating Node Failure

Abstract

In Wireless Sensor Networks (WSNs) sensor nodes often operate unattended in a collaborative manner to perform some tasks. In many applications, the network is deployed in harsh environments such as battlefield where the nodes are susceptible to damage. In addition, nodes may fail due to energy depletion and breakdown in the onboard electronics. The failure of nodes may have major consequences. First, some areas may be left uncovered. Second, the fidelity of the collected data gets degraded. And finally, the network may get partitioned into disjoint segments. In particular, losing network connectivity has a very negative effect on the applications since it prevents data exchange and hinders coordination among some nodes. Therefore, restoring the overall network connectivity with the least resource overhead and performance impact is very crucial. This chapter focuses on network topology management techniques for tolerating node failures. It analyzes the effects of node failure on network connectivity in WSNs, categorizes recently published recovery schemes, and outlines related open issues.