International Journal of Computer Applications (0975 – 8887) Volume 90 – No 11, March 2014 5 Realistic Vehicular Mobility Impact of FTM, IDM, IDM-IM and IDM-LC on VANETs Md. Habibur Rahman Dept. of Computer Science AIUB, Bangladesh Md. Monzur Morshed TigerHATS Dhaka, Bangladesh Meftah Ur Rahman Dept. of Computer Science George Mason University, USA ABSTRACT VANETs are composed of a number of vehicles moving on city roads, able to interconnect with one another without a fixed infrastructure. Improvisation of a new vehicular communication system should entitle a node to travel safely with high speed mobility while maintaining seamless interconnectivity. To evaluate the impact of mobility models such as FTM, IDM, IDM-IM and IDM-LC on VANETs routing protocol, VanetMobiSim is introduced to design a realistic vehicular mobility model for an urban scenario of Dhaka city. The experimental results suggest several issues e.g. lower packet drop rate, delay, jitter and route cost, etc are required to be considered before preparing a realistic application of VANET. The simulation results have been measured by different performance metrics such as drop, delay, jitter, round-trip time, throughput, route cost and mean hop etc. Keywords VANET; AODV; AOMDV; DYMO; OLSR; FTM; IDM-IM; IDM-LC; IDM; IEEE 802.11p; 1. INTRODUCTION Vehicular Ad-Hoc Network (VANET) is an extension of Mobile Ad-Hoc Network (MANET). It characterizes a rapidly progressive research area. It is regarded as an extreme case of mobile ad hoc network. In vehicular ad hoc networks (VANETs), vehicles communicate with roadside units (RSUs), referred to as vehicle-to-infrastructure (V2I) communications. In addition, vehicles can communicate with each other in an infrastructure less mode, referred to as vehicle-to-vehicle (V2V) communications [1]. It is a vehicular communication system for traffic safety, transport efficiency and data service. It enables public safety applications that can preserve lives and advance traffic flow [2]. Compared to MANETs, VANETs simulation provides some unique features such as highly dynamic topology, frequently disconnected network, patterned mobility, propagation model, on-board sensors, unlimited battery power and storage in a vehicular environment [3]. VANETs routing protocols can be categorized into topology-based and geographic (Position- based) routing protocol. Topology-based routing protocols are used for links’ information that exists in the network to do packet forwarding. It can be divided into proactive and reactive routing protocol. The performance of the VANET routing protocol can vary by additional reasons such as communication mode, vehicle/node density fluctuations, and vehicle/node mobility [4]. The node mobility can be expressed as node position, velocity, acceleration and deceleration in existence of neighboring nodes, line up at road intersections, traffic jam made by cross roads, traffic lights, node density and traffic congestion [5]. It is tough to look at those factors, particularly in an extreme mobility case. The IEEE 802.11p offers various stages of service importance based on different type of traffic pattern [1]. VanetMobiSim can provide the facility to design a real world mobility scenario of a particular area. It can be applied to dissect the traffic of a metropolis or a particular country. In this study, VanetMobiSim has been used to design a realistic vehicular mobility pattern for vehicular communications. For experimental evaluations, it is compared according to the impact of Fluid Traffic Model (FTM), Intelligent Driver Model (IDM), Intelligent Driver Model with Intersection Management (IDM-IM) and Intelligent Driver Model with Lane Changes (IDM-LC) etc. While doing this experiment, AODV, AOMDV, DYMO and OLSR routing protocols with respect to dissimilar parameter of QoS metrics have been used. 2. RELATED WORK Numerous surveys have been conducted to assess the performance of VANETs using several routing protocols along with different mobility models. In [4], the author has assessed the performance of Vehicular Ad-Hoc Networks using clustering of three different regions (urban, suburban and industrial) and traffic lights into the IDM-IM by AOMDV and AODV routing protocols with two dissimilar cases of traffic pattern. But the author has used existing IEEE 802.11b protocol instead of IEEE 802.11p MAC protocols. It is known that Wireless Access in Vehicular Environments (WAVE) or IEEE 802.11p provides enhancements to the physical and MAC layers. Likewise, several researchers use Two Ray Ground propagation model with IEEE 802.11b MAC protocol for comparing VANETs performance using different routing protocol, traffic pattern and various mobility models [5-9]. W. Alasmary et al. [1] presented the impact of mobility in IEEE 802.11p infrastructureless vehicular networks by investigating certain mobility factors. In their work, they indicated that relative speed has an important impact on channel access at the MAC layer, brushing off the number of communicating nodes. In [10], the authors have offered that 802.11p gives effective service differentiation mechanism that can be appropriate for the mission-critical ITS application. They evaluated the MAC layer performance without putting on any realistic vehicular mobility model for VANETs. V. Cabrera et al. [11] suggested some guidelines which could improve the performance of VANET routing such as store-carry-forward paradigm, beacons dependency, add useful information and careful selection of forwarding criteria. In their study, they have evaluated simulation-based study subject to vehicular mobility patterns. 3. REVIEW OF ROUTING PROTOCOLS Ad-Hoc On-demand Distance Vector (AODV) routing protocol maintains routing tables with single entry at each destination. When a source node stops sending data packet,