A Virtual Spanner for Efficient Face Routing in Multihop Wireless Networks

Geographic routing for ad hoc and sensor networks has gained a lot of momentum during the last few years. In this scheme routes are created locally by each individual node, just based on the position of the destination and its local neighbors. To do that, a node selects its best neighbor (according to some metric) out of those being closer than itself to the destination. This operation is called greedy mode. When a node has no such neighbors, it enters into face routing mode. However, for face routing to work properly, the underlying graph needs to be planarized by removing crossing edges, which may eventually be very good from the routing metric point-of-view. In this paper, we introduce a new localized scheme to build a planar virtual spanner in a simple and efficient way, with low control overhead. The produced virtual spanner allows face routing to be executed, without the need to remove any of the original links in the network. Thus, the best links according to the routing metric can still be used, Our simulation results show that by performing face routing over the virtual spanner, we manage to enhance the routing performance both for greedy-face-greedy routing and face routing between a 40 to 60% compared to existing planarity tests.