The DYMO Routing Protocol in VANET Scenarios

Coupling Vehicular Ad Hoc Networks (VANETs) with wired networks such as the Internet via access points creates a difficult mix of highly mobile nodes and a static infrastructure. In order to evaluate the performance of typical ad hoc routing protocols-in particular, we used Dynamic MANET On Demand (DYMO)-in such VANET scenarios, we combined microsimulation of road traffic and event-driven network simulation. Thus, we were able to analyze protocols of the Internet protocol suite in VANET scenarios with highly accurate mobility models. Varying parameters of DYMO for a multitude of traffic and communication scenarios helped point out approaches for improving the overall performance and revealed problems with the deployment. It could be shown that in realistic scenarios, even for medium densities of active nodes and low network load, overload behavior leads to a drastic decrease of the perceived network quality. Cross-layer optimization of transport and routing protocols therefore seems highly advisable.