Diffuse: A topology building engine for wireless sensor networks

In wireless sensor networks, multihop routing is commonly performed through a routing tree. Eventually, the routing tree needs to be rebuilt to accommodate failures, balance the energy consumption, or improve data aggregation. Most of the current solutions do not detect when the routing topology needs to be rebuilt. In this work, we propose an inference engine, called Diffuse, that uses information fusion techniques to detect when the routing topology needs to be rebuilt. Although the Diffuse applicability is ample, as a proof of concept, we use it to provide a fault-tolerant routing tree. Our solution is based on the data traffic that is pre-processed with a tunable moving average filter and translated into evidences that indicate failure probabilities. These evidences are combined using the Dempster-Shafer theory to determine when the topology needs to be rebuilt. We provide theoretical bounds for our proposed solution that is evaluated through simulation. Our experiments show that, in some cases, our solution can reduce the control traffic by a scale factor of 5. (C) 2007 Elsevier B.V. All rights reserved.