Topology Maintenance of Wireless Sensor Networks in Node Failure-prone Environments

A critical issue in wireless sensor networks is topology management and maintaining connectivity throughout the network and having a sufficient network lifetime in particular. There have been many topology management schemes proposed. Most of them conserve energy by periodically putting nodes to sleep. One consideration often overlooked is the fact that sensor nodes will fail, especially in harsh environments. In this paper, a modification to an existing topology management scheme, Naps, is proposed to ensure very minimal data loss while also handling node failures. The idea is to conserve energy to prolong the lifetime of the nodes and the sensor network while maintaining a constantly connected sensor network. Simulation results demonstrate that failed nodes do not have a significant impact on network connectivity or lifetime, at least in a random, uniform deployment. The paper also illustrates that two different approaches taken in the Naps modification for compensating for failed nodes produce similar results.