A survey on intersection-based routing protocols in city scenario of VANETs

As is known, the intersection-based geographic routing protocol is a promising solution to the information dissemination in realistic city environments. Also, there exists a series of special issues for VANETs urban area. Aiming to tackle these issues, many such routing protocols have been proposed in academia. In this paper, we present four important issues for city scenarios which not only strongly affect the performance of routing protocols, but also will be key factors to prompt us to redesign more suitable routing protocols. Those issues include intermittent connectivity, traffic light at intersections, three-dimensional and traffic accident city scenarios. Then we give a survey on recent intersection-based geographic routing protocols and explore how those issues impact the performance of these protocols. In order to better reflect the influence of these issues, we perform a simulation-based analysis. We evaluate the performance of the existing routing protocols including GPCR, GyTAR, STAR, and TDR in city scenarios with above issues. Simulation results prove that these scenarios affect the performance of routing protocol significantly. Finally, we put forward guidelines which are conductive for designing VANETs routing protocols.