Topology-based routing for Xmesh in wireless sensor networks

Large wireless sensor networks can contain hundreds or thousands of sensor nodes. Due to wireless sensor network's properties of low-energy-efficiency, large-scale, low cost, and lossy nature, the development of efficient routing protocols for these large and dense wireless sensor networks is an interesting research topic. This research focuses on the design and implementation of protocols for dense and wireless sensor networks. More specifically, we propose to combine an underlying topology with Xmesh, the multihop routing strategy of Crossbow Technology's motes. In an effort to limit the path lengths, we propose to impose an underlying connectivity graph for Xmesh. The underlying connectivity graph is a virtual topology of the network, hence the name "topology-based routing." Instead of being always forwarded to the node with the best link quality among all neighbors, a packet is being routed according to the shortest path routing of the underlying graph which guarantees a bounded path length. Cayley graphs from the Borel subgroup have been known as the densest degree-4 graphs and all Cayley graphs are vertex transitive. In this work, we propose a topology-based routing for Xmesh with Cayley graphs as the underlying topology. We show that, indeed, by imposing a Cayley graph as an underlying graph, the average path lengths between nodes is smaller and that the averaged power consumed is less than the original Xmesh.