Geographic Routing Around Obstacles in Wireless Sensor Networks

Geographic routing is becoming the protocol of choice for many sensor network applications. The current state of the art is unsatisfactory: some algorithms are very efficient, however they require a preliminary planarization of the communication graph. Planarization induces overhead and is not realistic in many scenarios. On the other hand, georouting algorithms which do not rely on planarization have fairly low success rates and either fail to route messages around all but the simplest obstacles or have a high topology control overhead (e.g. contour detection algorithms). To overcome these limitations, we propose GRIC [PN07], the first lightweight and efficient on demand (i.e. all-to-all) geographic routing algorithm which does not require planarization and has almost 100% delivery rates (when no obstacles are added). Furthermore, the excellent behavior of our algorithm is maintained even in the presence of large convex obstacles. The case of hard concave obstacles is also studied; such obstacles are hard instances for which performance diminishes.