Vehicular networks are expected to be one of the major new application areas for wireless and Internet services. There are more than 600 million vehicles worldwide and these will be networked to achieve improvements to safety, traffic management, navigation, and user convenience. Vehicular networks (VANETs) have several elements in common with ad hoc mesh networks, but also have unique new requirements including high mobility, rapidly changing topology, multiple usage modes (vehicle-to-infrastructure [V2I] and vehicle-to-vehicle [V2V]), and the central importance of geo-location.
In the first part of this chapter, emerging VANETs are shown to be unique in the broad family of MANETs (Mobile Ad Hoc Networks). VANET services are reviewed and classified. A location-aware content distribution (“car-torrent”) is then presented. Next, vehicle urban sensing is showcased for applications that range from traffic congestion/pollution measurements to distributed civilian surveillance. MobEyes, an urban surveillance application that supports forensic investigations, is then described and contrasted to other urban sensing projects.
In the second part of the chapter, the enabling VANET protocols are reviewed. First, physical and MAC layer standards for vehicular communications (DSRC, WAVE, and IEEE 802.11p) are reviewed. Then, new VANET network level protocol requirements are identified and solutions are discussed. Geo-location-based protocol architectures are introduced and briefly touch on complementary techniques such as geo-based handoff and geo-based beam adaptation for smart antennas. Security and privacy issues are addresses, with particular attention to location privacy. These protocols are illustrated with urban sensing applications.