Road Side Unit coverage extension for data dissemination in VANETs

Data dissemination is a key component of Infotainment and safety services in Vehicular Ad Hoc Networks. For infotainment services data dissemination starts from a Road Side Unit (RSU) and propagates to a multiplicity of On Board Units (OBU). A RSU typically can reach with a single hop only a fraction of the interested vehicles. Multi-hop, inter-vehicle communications is necessary to reach vehicles in the whole area that could be interested in the service. For an efficient data dissemination both the number of forwarding vehicles and the number of not covered ones shall be kept down. In this work we study the extension of the RSU coverage area via a simple data dissemination defined for urban scenarios. The proposed forwarding algorithm relies only on information local to the forwarding OBU. We show that in our case studies representing urban structures the protocol guarantees a good RSU coverage extension (in the order of 20 times the transmission area of the RSU) with a very low percentage of vehicles not reached by the disseminated data.