Infotainment applications support in VANET

Vehicular Ad-Hoc Networks (VANET) are attracting the interest of network operators and service providers for the provision of infotainment services [1]. The communication standard that will be used for inter-vehicular communications is the IEEE 802.11p [2] also known as Wireless Access in Vehicular Environments (WAVE). The WAVE protocol standards (802.11p /1609) aim at providing a set of specifications to allow interoperability between wireless devices on board of vehicles (On-Board Unit, OBU) and devices located near the roads (Road Side Unit, RSU). We can distinguish between safety related messages, which need to be transferred in real time (fractions of seconds), but affecting an area of the order of the coverage area of a RSU/OBU, and messages related to traffic information, road conditions, local utility information and so forth, which should be disseminated in an area of several kilometers, but having less stringent delay requirements (seconds or tens of seconds). In these kind of services, also called Non-Public Safety services, we can list traffic information, electronic toll collection, advertisement, parking lot payment, video streaming services and many others. A key component of the infotainment services is the data dissemination that allows all users on board of vehicles to receive information relevant to services available in the considered area (we name it service area). In the VANET context, 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, related to its radio transmission range. Multi-hop, inter-vehicle communications is necessary to reach vehicles in the whole area that could be interested in the service. The aim is to cover an extended area around the RSU that has originated the contents.