Evaluating VANET routing in urban environments

Vehicular Ad-hoc Networks (VANETs) are a class of Mobile Ad-hoc Networks (MANETs) incorporated into moving vehicles. Nodes communicate with both and infrastructure to provide Intelligent Transportation Systems (ITS) for the purpose of improving safety and comfort. Efficient and adaptive routing protocols are essential for achieving reliable and scalable network performance. However, routing in VANETs is challenging due to the high-speed movement of vehicles, which results in frequent network topology changes. This paper provides an in-depth evaluation of three well-known MANET routing protocols, AODV, OLSR and GPSR, in VANET with urban environment setup. We compare their performance using three metrics: drop burst length (DBL), delay and delivery ratio (PDR). The simulations are carried out using NS2 and SUMO simulators platforms, with scenarios configured to reflect real-world conditions. The results show that OLSR is able to achieve a shorter DBL and demonstrates higher PDR performance comparing to AODV and GPSR under low network load. However, with GPSR, the network shows more stable PDR under medium and high network load. In term of delay it is outperformed by GPSR, which delivers packets with the shortest delay.