Impact of link quality estimation errors on routing metrics for wireless sensor networks

Link quality-based routing protocols are often utilized in wireless sensor networks. Link quality estimation algorithms are used to retrieve information about the link quality, which is evaluated to choose the best available path. Concurrently, recent work has revealed severe inaccuracies in link quality estimations provided by modern short-range wireless devices. The sensitivity of routing protocols to such errors in the estimation of the link quality has not been considered so far. In this paper, we define two main classes of link quality-based routing metrics and examine these classes. We present a method to estimate the sensitivity of routing metrics to link quality estimation errors and confirm this method by simulations. Some routing metrics are surprisingly strong influenced by estimation errors. This finding questions the applicability of these protocols in large-scale networks and necessitates that the impact of link quality estimation errors is explicitly regarded in future developments of link-quality-based routing metrics to create more robust metrics. Our proposed method to estimate the sensitivity of routing metrics on link quality estimation errors shows to be helpful here.