Performance, Study of Node-Disjoint Multipath Routing in Vehicular Ad Hoc Networks

Many multipath routing schemes have recently been proposed to improve the performance of wireless networks. Multipath routing is supposed to reduce the end-to-end packet delay and increase the packet delivery ratio. Therefore, it can also improve the packet delivery ratio in vehicular ad hoc networks (VANETs) when the mobility of relaying vehicles is unknown. However, in wireless networks, multiple paths are exposed to mutual interference or path coupling, which impairs efficiency. The intriguing question is whether the node-disjoint multipath routing really helps. In this paper, we examine the performance of node-disjoint multipath routing in VANETs. Through extensive simulations, we explore the effect of mutual interference on the behavior of node-disjoint paths. It is shown that whether node-disjoint paths are able to improve performance, compared with the single path, is determined by path coupling and the source-destination distance. Results show that node-disjoint multipath routing can be applied to VANETs to substantially improve performance in terms of delay and packet delivery probability only if the node-disjoint paths are properly chosen.