| dc.description.abstract | Emerging applications in the realm of Intelligent Transportation systems, such as traffic congestion management and vehicle rerouting, weather alerts, and infotainment via multimedia streaming, require timely and reliable dissemination of bulky data. Vehicle mobility, unreliable wireless communications, and short range of communications with infrastructure entities, such as road-side units (RSUs), make it hard to satisfy these application properties in a scalable manner. For example, the high mobility of a vehicle results in less than a minute of connectivity with a RSU that have a range of just 1,000 meters and with vehicles moving in clusters, each vehicle will be served only a fraction of its connected time.
This thesis makes three contributions. With simulation results we show that in this time window, it is impossible for multimedia related applications to work no matter what the speed of the cluster is. We analyze our simulation results and conclude that cooperation among cars in a cluster and cooperation among RSUs along the road have a great potential in overcoming these challenges. We then propose a two-level event brokering framework. At the first level, a collection of RSUs and Internet-based nodes form a static brokering network, which cooperate to estimate the expected connectivity windows of vehicles with different RSUs, and accordingly segment and disseminate application-level information to the different RSUs along the path of the vehicles. At the second level, the vehicle density is leveraged to superimpose a brokering network over the dynamic vehicular ad-hoc network to scalably disseminate information. Events are routed not only by content and interested subscribers but also by their priority level. | |
