An Improved Realistic Mobility Model and Mechanism for VANET Based on SUMO and NS3 Collaborative Simulations Yunyun Su Shanghai Key Laboratory of Trustworthy Computing East China Normal University Shanghai, China e-mail: syysnowwhite@163.com Haibin Cai* Shanghai Key Laboratory of Trustworthy Computing East China Normal University Shanghai, China e-mail: hbcai@sei.ecnu.edu.cn Jingmin Shi Shanghai Key Laboratory of Trustworthy Computing East China Normal University Shanghai, China e-mail: cherrysjm@outlook.com Abstract—The information field is undergoing a new round of technological revolution from the Internet to the Internet of things. Vehicle ad-hoc network (VANET) ， an application of the internet of things using in Intelligent Transportation System (ITS), has already attracted broad attention in the world in recent years. It mainly provides communications between vehicle-to-vehicle and vehicle-to- infrastructure, which significantly improve road transport efficiency, reduce energy consumption and ease traffic congestion. In this paper, we developed a client to make SUMO and NS3 work parallel by TraCI (Traffic Control Interface) in NS3. It helps NS3 get SUMO’s information and sends instructions to change the states of vehicles and traffic lights. We present a realistic road traffic model with kinds of vehicles and intelligent traffic lights. The model is built in SUMO (Simulation of Urban Mobility). We use OpenStreetMap to generate a realistic map near the bund in Shanghai. The traffic flow is built according to a survey which makes us get meaningful and reliable statistics. A mechanism of changing the traffic lights dynamically is introduced to minimize traffic jams and give high priority to emergency vehicle. As a result, the waiting time and the duration of the vehicles in the scenario have reduced significantly after using the mechanism. The emergency vehicle’s waiting time is less than others. Keywords—VANET; SUMO; NS3; OpenstreetMap; TraCI; Intelligent Traffic Lights; I. INTRODUCTION Nowadays traffic problems like collisions, traffic jams, energy consumption and emission have been a hot issue in our daily life due to the increasing number of cars. According to the latest statistical data [1] by the United Nations, millions of people lost their lives in fatal accidents in the world every year. People waste too much time in traffic jams which also cause the environmental pollution. The emergency vehicles like ambulance, fire engine will be blocked in the street and they can’t go as fast as possible which may lead to a catastrophe. It is obvious that alleviating the traffic problem will bring great convenience to our life and save lots of lives. VANET technology is an effective way to solve the problems. It is an important intersection of the Internet of things and telematics in new strategic industries. A solution to this problem is to install intelligent traffic lights to change the states dynamically according to the actual traffic conditions to minimize traffic jams and give high priority to emergency vehicle. Through the wireless technology of electronic equipment installed in vehicles, vehicle-to-vehicle communication becomes a new way for people to chat with each other. VANET can get and use all the vehicles’ static and dynamic information effectively, realizing vehicle-to-vehicle and vehicle-to-infrastructure information exchanging as Fig. 1 shows. Fig 1. Common Intersection Scene of VANET It is quite difficult for us to analyze the traffic problems and find out the solutions in real life. Besides the complex road system, the expense is high and it’s too dangerous to test in real life. So, the simulation technology plays an 978-1-4799-7615-7/14/$31.00 ©2014 IEEE