A VANET routing based on the real-time road vehicle density in the city environment

The intelligent transportation system (ITS) can enhance the driver's safety by providing safety-related information such as traffic conditions and accident information to drivers. The vehicular ad hoc network (VANET) is an essential technology for the deployment of ITS. And, for the reliable delivery of safety-related information to vehicles in the VANET, a reliable VANET routing protocol is required. VANET routing is challenging since it is fundamentally different from conventional ad hoc networks; the vehicles move fast, and the network topology changes rapidly causing intermittent link connectivity. In this paper, we propose a routing protocol that works based on the real-time road vehicle density in order to provide fast and reliable communications so that it adapts to the dynamic vehicular city environment. In the proposed routing mechanism, each vehicle computes the vehicle density of the road to which it belongs by using beacon messages and the road information table. Based on the real-time road vehicle density information, each vehicle establishes a reliable route for packet delivery. In order to evaluate the performance of the proposed mechanism, we compare our proposed mechanism with GPSR through NS-2 based simulations and show that our mechanism outperforms GPSR in terms of delivery success rate and routing overhead.¹