AnIntegratedMobility and TrafficModel forVehicular

Abstract

Ad-hoc wireless communication among highly dynamic, mobile nodes in a urban network is a critical capability for a wide range of important applications including automated vehicles, real-time traffic monitoring and vehicular safety applications. When evaluating application performance in simulation, a realistic mobility model for vehicular ad-hoc networks (VANETs) is critical for accurate results. This paper analyzes ad-hoc wireless network performance in a vehicular network in which nodes move according to a simplified vehicular traffic model on roads defined by real map data. We show that when nodes move according to our street mobility model, STRAW, network performance is significantly different from that of the commonly used random waypoint model. We also demonstrate that protocol performance varies with the type of urban environment. Finally, we use these results to argue for the development of integrated vehicular and network traffic simulators to evaluate vehicular ad-hoc network applications, particularly when the information passed through the network affects node mobility. 1. INTRODUCTION The community is increasingly interested in developing network protocols and services for vehicular ad-hoc networks (VANETs). Due in part to the prohibitive cost of deploying and implementing such systems in the real world, most research in this area relies on simulation for evaluation. A key component of these simulations is a realistic vehicular mobility model that ensures conclusions drawn from such experiments will carry through to real deployments. Unlike many other mobile ad-hoc environments where node movement occurs in an open field (such as conference rooms and caf´ es), vehicular nodes are constrained to streets often separated by buildings, trees or other objects. Street layouts and different obstructions increase the average distance between nodes and, in most cases, reduce the overall signal strength received at each node. We argue that a Permission to