Curve-based planar graph routing with guaranteed delivery in multihop wireless networks

Localized geographic routing schemes operating on planar graphs promise scalability for use within large multihop wireless networks. Existing schemes base routing path construction on faces defined by the planar graph. Once running on a particular planar graph, none of the existing schemes is flexible enough to adapt the sequence of faces visited by the constructed path. Thus, real-world constraints such as network congestion, limited node energy levels, or non-cooperation of nodes might severely impact the performance and the robustness of existing planar graph routing variants. To address this problem, we extend planar graph routing with one further degree of freedom: control over the sequence of visited faces. Basically, our face routing extension now follows a sequence of faces intersected by any curve we can freely adjust. We investigate basic schemes for choosing curves dealing with imperfections in the network, and derive algorithms for routing and forwarding along these curves. We analytically prove that our scheme is loop free and allows for guaranteed delivery in arbitrary planar connected graphs. We implement curve-based routing and show its feasibility by means of a simulation study. As a proof-of-concept scenario, we investigate the case of non-cooperating nodes. Our results show that curve-based routing is able to sustain the delivery of packets where traditional schemes fail.