Evaluation of Mobility Models For Vehicular Ad-Hoc Network Simulations

There is a growing interest in deployment and evaluation of routing protocols for Vehicular Ad-Hoc Wireless Networks (VANETs) in urban contexts. The mobility model of nodes is one of the most important factors that impacts the evaluation of any wireless ad-hoc routing protocol using simulations. In this paper we make the case that the state-of-the-art simulation techniques do not effectively model many important factors that come into play in urban mobile environment. We present two new simple mobility models for VANETs that account for constrained movement pattern of vehicles on urban streets. Using traffic patterns and street maps, we perform a comprehensive comparison of the impact of our two new mobility models against two earlier mobility models. Unlike prior results in this area, our results demonstrate that the mobility model used in simulation does significantly impact the delivery ratio and packet delays in VANETs. With plenty of room for further improvement, our models provide a sound starting point for the development of more realistic and accurate mobility and obstacle models for VANET simulations.