Issues and Challenges in VANET Routing Protocols

Intelligent transportation systems (ITS) are becoming more popular due to the demand for advanced cyber-physical systems and comfort applications and services needed for use in autonomous vehicles. Vehicular ad hoc Networks (VANETs) are an essential part of ITS, as they support vehicle-to-vehicle and vehicle-to-infrastructure data communication. The performance of a VANET solely depends on the routing protocols in the network layer, which provide efficient and effective data communication. In this paper, we survey the most recent issues surrounding efficient routing protocols that are suitable for VANETs. We also address the pros and cons of these protocols in terms of scalability, quality of services, security and privacy, energy efficiency, transmission bandwidth limitation, and broadcasting issues.