Optimizing Architecture of Vehicle to Infrastructure Communication

Abstract

Vehicular Ad-hoc Networks are self-organizing networks established among vehicles equipped with communication facilities. Due to recent advancements in vehicular technologies vehic- ular communication has emerged. For a rich set of applications implementing Intelligent Highways, like application related to road safety, tra c monitoring and management, road disaster mitigation etc. the road side infrastructure plays a vital role for any VANET. This is the reason that e cient communication between the vehicles and the road side infras- tructure is required. Meeting this requirement becomes very di cult as nodes in a VANET are highly mobile and thus the network topology is highly dynamic. In such a state of af- fairs it is required to optimize the vehicle to infrastructure communication to achieve better e ciency. This project aims to achieve a better vehicle to infrastructure communication. The application under consideration is providing a zero tra c lane (Z-Lane) for an ambu- lance. To achieve the goal rst a suitable vehicular mobility model is identi ed. Krauss Mobility Model is used for simulation of road tra c scenario. The scenarios are imple- mented with the help of Simulation of Urban Mobility (SUMO) which is a road tra c simulator based on Krauss Mobility Model. For the normal working of the said application, Ambulances using the service are assumed to have their MAC address registered. Ambu- lance driver will be setting the destination coordinates (this information will be carried in the routing protocol header for further decision making) in the application unit and will trigger the infrastructure informing its presence. On reception of this trigger, road side infrastructure broadcasts alert messages informing the vehicle drivers to vacant the lane. By doing so the ambulance will get a zero tra c lane in advance. The problem addressed in this project is the scenario where no infrastructure is present in the range of ambulance. In this case, the trigger from the ambulance must reach the nearest infrastructure as early as possible for e cient working of the application. For this purpose vehicle to vehicle communication is used. Various routing algorithms have been analyzed in terms of their end to end delay and packet delivery fraction. Ad-hoc On De- mand Distance Vector (AODV) routing algorithm is chosen for the said communication. The AODV protocol has signi cant amount of end to end delay. The project aims to re- duce the Route REQuest (RREQ) packet (this carries information regarding the destination position also) generation in AODV. This is done by modifying the protocol in such a way that RREQ packets are sent only to the neighbor which gives highest advancement towards the destination. If no such neighbor is found the store carry forward approach is used for packet advancement. The simulation results of the implementation of modi ed AODV shows that the number of RREQ packets reduces drastically and in turn end-to-end delay also reduces. The network tra c simulation is done with the help of Network Simulator - 2 (NS-2). To generate the scenario in SUMO and converting it into NS-2 readable form MObiligy generator for VEhicular network (MOVE) is used.