The upcoming models of vehicles will be able to communicate with each other and will thus be able to share and/or transfer information. A vehicular ad hoc network (VANET) is an application of this vehicular communication that leads to an intelligent transportation system (ITS). Vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) are the two distinct types of vehicular ad hoc networks (VANET). V2V and V2I technologies are together known as V2X and are recently being tested. Continuous research to enhance routing considers different characteristics and exciting aspects of VANETs. The proposed schemes are classified based on the operational scenario. A survey of proposed routing schemes in the last eight years is presented to determine the design considerations and the approach used in every proposed system, along with their shortcomings. This survey will assist new scholars in this field to analyze existing state-of-the-art systems. The table at the end of each routing scheme shows the proposed routing scheme’s simulation, routing, and scenario parameters. This paper also reviews VANET technology, its role in the intelligent transportation system, recent development in the field, and the timeline for implementation of the system.

Routing protocols are an essential component of vehicular ad hoc networks. Software-defined networks and name data networks are new aspects of routing that are coming to the fore as Vehicular Ad Hoc Network technology evolves. Data Network-based VANET routing protocols and Software Defined Network-based VANET routing protocols have been developed in recent research. These newly developed protocols must be part of VANET routing protocol surveys. The taxonomy of traditional routing protocols must take these innovations into account. To the best of our knowledge, no such taxonomy exists at the moment. We present a new taxonomy of routing protocols based on the additional routing aspects of Software-Defined Networks and Named Data Networks. All traditional routing protocols are kept in a single category. This research work aims to update the existing taxonomy of routing protocols with the newly adopted aspects of research in routing. Advanced routing schemes are selected for the survey from each category to evaluate new research results in VANET routing. This article also describes future directions for VANET/ITS routing research.