A Survey of Vehicular Cloud Research: Trends, Applications and Challenges

The past decade has seen the emergence of Vehicular Clouds as a topic of research in its own right. Vehicular clouds were inspired by the reality of present-day vehicles featuring an impressive array of on-board compute, storage and sensing capabilities and by the insight that these on-board capabilities are a vast untapped resource that, at the moment, is wasted. Harvesting these vehicular resources and putting them to work in a meaningful and productive way promises to have a significant and lasting societal impact. One of the defining ways in which vehicular clouds differ from conventional clouds is resource volatility. As vehicles enter and leave the cloud, new compute resources become available while others depart, creating a volatile environment where reasoning about fundamental performance metrics becomes very challenging. Given that vehicular clouds and their numerous variants have becomes a very active field of research, this seems to be a good moment to survey the state of the art of vehicular cloud research. In this survey, we adopt an inclusive rather than an exclusive definition of various flavors of vehicular clouds. Vehicular clouds, in their many incarnations, have a huge array of potential applications. In order to bring this potential to fruition, significant research challenges have to be overcome. With this in mind, this survey identifies promising applications and draws attention to a number of research challenges facing the vehicular clouds community at large.