Measuring and guaranteeing quality of barrier-coverage in wireless sensor networks

Abstract

Sensors may fail due to various reasons such as heat, malicious activity, environmental hazards, extended use, and lack of power. As more and more sensors fail, certain desired properties such as barrier coverage will diminish and eventually fall below a desired level. In such a case, the network will have to be repaired. It is therefore desirable to have mechanisms to monitor network properties. In this paper, we are interested in measuring the quality of barrier coverage. In the literature, researchers only consider whether or not a sensor network provides barrier coverage. This is equivalent to measuring its quality as either 0 or 1. We believe quality of barrier coverage is not binary and propose a metric for measuring it. If the measured quality is short of a desired value, we further identify all local regions that need to be repaired. The identified regions are minimum in the sense that if one of them is not repaired then the resulting network will still be short of quality. We also discuss how to actually repair a region.