Congestion and Position Aware Dynamic Routing for the Internet of Vehicles

The coupling of packet forwarding, Internet gateway (IGW) selection, and vehicle mobility in the Internet of Vehicles (IoV) presents challenges for multi-hop routing. Particularly, IGWs and vehicles near IGWs are most likely to be congested, since all the Internet traffic loads converge at IGWs in IoV. To this end, we propose a distance-weighted back-pressure dynamic routing (DBDR), which prioritizes the vehicles that are close to the destination and have a large backlog differential of buffer queues to provide dynamic hop-by-hop forwarding. DBDR is also jointly designed with multi-hop IGW discovery and vehicle mobility management to implement both uplink and downlink forwarding for Internet services. Our analysis using Lyapunov drift theory proves that DBDR achieves the network stability on the buffer queues and the network capacity. Simulations in a practical road scenario using NS-2 and VanetMobiSim show that DBDR outperforms the existing protocols in terms of packet delivery ratio, throughput, and success rate of HTTP requests/responses, as well as average packet delay when the network becomes congested.