A Multi-path Extension to RDV Routing Scheme for Static-node-Assisted Vehicular Networks

Vehicular Ad-hoc NETworks (VANETs) in sparse vehicles scenarios can be regarded as a kind of Delay Tolerant Networks (DTNs), and how to provide reliable and efficient communications over them has been extensively studied. Past studies such as SADV and RDV showed that the assistance of low-cost unwired static nodes located at intersections, which work as routers to provide distance-vector or link-state routing functions, significantly improves the communication performance such as delivery ratio and delivery delay. Especially, RDV provides any previously configured value of expected packet delivery ratio by creating the required number of duplicated packet copies on the shortest paths. Despite of the high delivery ratio achievement, RDV still has problems, that is, traffic concentration in the shortest paths and its large delivery delay. In this paper, we extend RDV by using multiple paths to avoid packet concentration as well as to improve delivery delay while preserving the function to provide the preconfigured expected delivery ratio. Evaluation results show that the proposed method MP-RDV (Multi-Path RDV) achieves high load-balancing performance to provide better network capacity, lower delivery delay, and higher fault tolerance against topology changes.