New Holes and Boundary Detection Algorithm for Heterogeneous Wireless Sensor Networks

Abstract

Hole is an area in wireless sensor network (WSN) around which nodes cease to sense or communicatedue to drainage of battery or any fault, either temporary or permanent. Holes impair sensing andcommunication functions of network; thus their identication is a major concern. In this paper, adistributed solution is proposed for detecting boundaries and holes in the WSN using only the nodesconnectivity information and estimated distance between nodes. The run of our protocol is dividedinto four main phases. In the rst phase, each node discovers its coverage neighbors and collects theirinformation. In the second phase, each node communicates with its neighbors to nd whether its sensingrange is fully covered by the sensing ranges of its neighbors. In the third phase, the boundary nodesconnect with each other to complete the boundary information. In the fourth phase, a boundary subgraphamongst boundary nodes is constructed and classied either as an interior or an exterior boundary.Simulation results show that our approach improves the energy and reduces the number of boundarynodes over existing algorithms.