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.