Geo-opportunistic routing for vehicular networks [Topics in Automotive Networking]

Road topology information has recently been used to assist geographic routing in urban vehicular environments to improve overall routing performance. However, the unreliable nature of wireless channels due to motion and obstructions still makes road topology assisted geographic routing challenging. In this article we begin by reviewing conventional road topology assisted geographic routing protocols, and investigate the robust routing protocols that address and help overcome the unreliable wireless channels. We then present topology-assisted geo-opportunistic routing that incorporates topology assisted geographic routing with opportunistic forwarding. That is, the routing protocol exploits the simultaneous packet receptions induced by the broadcast nature of the wireless medium and performs opportunistic forwarding via a subset of neighbors that have received the packet correctly. Our simulation results confirm TO-GO´s superior robustness to channel errors and collisions compared to conventional topology-assisted geographic routing protocols.