Location-Aided Gateway Advertisement and Discovery Protocol for VANets

Intelligent transportation systems (ITSs) are gaining momentum among researchers. ITS encompasses several technologies, including wireless communications, sensor networks, voice and data communication, real-time driving-assistant systems, etc. These state-of-the-art technologies are expected to pave the way for a plethora of vehicular network applications. However, ITS faces difficult issues when trying to widely deploy such networks and applications. The interconnection of different networks, even in the case of the Internet, is one of the main difficulties that is delaying the wide spread of vehicular networks. In this paper, we present a novel gateway discovery technique for vehicular ad hoc networks (VANets). Our protocol aims to provide an efficient hybrid adaptive Location-Aided Gateway Advertisement and Discovery (LAGAD) mechanism for VANets. First, it permits gateway clients to discover nearby gateways; then, gateways keep advertising themselves to their clients to permit client information about the route toward the discovered gateway without having to resort to reactive route discovery. We discuss the implementation of our algorithm and present its proof of correctness, in addition to the performance evaluation demonstrated through an extensive set of simulation experiments using a Manhattan mobility model. Our results indicate that our LAGAD scheme is scalable and that a significant success rate could be achieved using our algorithm while guaranteeing low response time (on the order of milliseconds) and low bandwidth usage when compared with other gateway discovery approaches. Moreover, our results indicate that LAGAD achieves a high delivery ratio of data packets, as well as a low end-to-end delay, and permits duplicate and ordered data packet reception at the destination gateway.