International Journal of Scientific & Engineering Research, Volume 5, Issue 4, April-2014 425 ISSN 2229-5518 IJSER © 2014 http://www.ijser.org Design of Reactive Routing Protocols to Improve the Performance of VANET P.S. Dinesh, J. Vijay Franklin Abstract— Vehicular Ad-Hoc Networks (VANET) is a subclass of Mobile ad-hoc networks which gives as an eminent method for Intelligent Transport System (ITS). The analysis of routing protocols in VANET is essential and basic for intelligent ITS. In this paper discussed the pros/cons and the applications of a typical routing protocol used for vehicular ad-hoc networks. It evaluates the backward designed purpose, and tracks the progression of routing protocols. In this paper, an effort has been made to evaluate the performance of vehicular networks by using two reactive routing protocols namely Ad-hoc On demand Distance Vector (AODV) and Dynamic Source Routing (DSR) are the detection algorithms which works as gateway and a geographical routing protocol namely Greedy Perimeter Stateless Routing (GPSR) which is used to update network topology information available to all nodes in VANETs for different scenarios. Comparisons of protocols are made on the basis of different parameters such as throughput, packet loss, packet delivery ratio and end-to- end delay using NS2 simulator. Index Terms— VANET, routing protocols, AODV, DSR, GPSR, QoS, Vehicle-to-Vehicle, Vehicle-to-Infrastructure. ——————————  —————————— 1 INTRODUCTION he recent technology of Vehicular networks represents a predominant novel category of wireless ad hoc networks that facilitate vehicles to exchange the information with each other on the roadside communications. Previously, driv- ers share their communication by means of voice, gestures, horns, and also with the examination of every one routes to control their activities. When the distance of the vehicle gets increase, then the analysis of vehicle communication is diffi- cult to manage. Hence the hand signals, semaphores and colored lights have been implemented by the traffic police for controlling and supervision of the traffic. For providing the safety communication “[13], [14]”, the mechanization of traffic signals and automobile indicators was deployed. Now a day, the drivers can able to share their traf- fic information and guidelines by using the car phones or ci- vilian propagation. Wireless communications are more suita- ble for exchanging the personalized and absolute information. VANET concentrate on all the issues which are interrelated to the connections and communications between vehicles. VANET also concentrates on the Wireless Access for the Ve- hicular Environment (WAVE) principle based on the emerg- ing IEEE 802.11p specification. VANET fundamentally enables Infrastructure-to-Vehicle (I2V), Vehicle-to-Infrastructure (V2I), and Vehicle-to-Vehicle (V2V) infrastructure. 2 NETWORK ARCHITECTURES Wireless ad-hoc networks are usually in the motion of mobility nature hence it do not rely on permanent infrastructure and propagation of information for communication. As like Wire- less ad-hoc networks VANETs also uses the same standard for highly self-motivated situation for exterior transportation. As shown in Figure. 1, the design network of VANETs is differen- tiated as three categories: pure cellular /WLAN, pure ad hoc, and hybrid. The permanent cellular gateways and the WLAN/WiMax access points at traffic intersections are used by VANETs. The permanent cellular gateways and the WLAN/WiMax access points are used to connect the vehicles with the Internet and also to gather traffic information during the process of routing. The pure cellular or Wireless LAN structure is shown in Figure 1 (a). While combining both cel- lular network and WLAN in the VANETs the access point is presented as well as 3G connection is also established. (a) Cellular/WLAN (b) Ad Hoc (c) Hybrid Fig 1. Architectures for Vehicular Network In Figure 1 (b) shows Vehicle to Vehicle communication for obtaining the defined goals, like blind crossing. In Figure.1 (c) the Hybrid architecture combines both the infrastructure networks and an ad-hoc network jointly for providing the probable solution for VANETs. By using WLAN and cellular capabilities as the gateways and mobile network routers “[1]”the vehicles with only WLAN capacity can able to com- municate with the other vehicles through multi-hop links con- nected to the network. The hybrid architecture can offers im- proved coverage, but with some problems of faultless transi- tion of the communication between dissimilar wireless sys- tems. T ———————————————— • Dinesh.P.S is currently pursuing masters degree program computer science and engineering in Bannari Amman Institute of Technology, AnnaUniversi- ty,India, PH-+919942984621. E-mail: dineshpudhu@mail.com • Dr. Vijay Franklin.J, Assistant Professor (Sr.G) department of computer science and engineering in Bannari Amman Institute of Technology, AnnaUniversity,India, PH-+919488470970. E-mail:jvfcse@mail.com IJSER