Rules of Designing Routing Metrics for Greedy,
Face, and Combined Greedy-Face Routing

Yujun Li, Yaling Yang, and Xianliang Lu

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Abstract—


Different geographic routing protocols have different requirements on routing metric designs to ensure proper operation.
Combining a wrong type of routing metrics with a geographic routing protocol may produce unexpected results, such as geographic
routing loops and unreachable nodes. In this paper, we propose a novel routing algebra system to investigate the compatibilities
between routing metrics and three geographic routing protocols including greedy, face, and combined greedy-face routing. Five
important algebraic properties, respectively, named odd symmetry, transitivity, strict order, source independence, and local minimum
freeness, are defined in this algebra system. Based on these algebraic properties, the necessary and sufficient conditions for loop-free,
delivery-guaranteed, and consistent routing are derived when greedy, face, and combined greedy-face routing serve as packet
forwarding schemes or as path discovery algorithms, respectively. Our work provides essential criteria for evaluating and designing
geographic routing protocols

for more ::-0>

http://doi.ieeecomputersociety10.1109/TMC.2009.171

http://ieeexplore.ieeeiel5/5061887/50618...er=5061907