Performance Analysis and Comparison of MANET Routing Protocols Kuljit Kaur 1 ,Swati Jindal 2 ,Lavneet Bansal 3 1 Department of Computer Engineering, GNDU, Amritsar 2 Computer Engineering, Guru Nanak Dev University, Amritsar 3 Department of Computer Engineering, MIMIT, Malout ABSTRACT-Advances in wireless technology and portable computing along with demands for greater user mobility have provided a major movement towards development of ad-hoc networks. The main Method for evaluating the performance of MANET’s is simulation. An extensive simulation is performed using NS-2 simulator and end to end delay, packet delivery ratio, packet loss ratio, throughput and jitter for Reactive protocols TORA,DSR and proactive protocol DSDV for TCP and CBR traffic patten are evaluated for different scenarios i.e. pause time, simulation time and no of nodes . At the end it is concluded that in case of TCP DSDV(Proactive) is best and in case of CBR DSR(Reactive) is best. Performance of TORA is average in all cases except packet loss. Keywords: TORA, DSR, DSDV, MANET, protocols, NS-2 simulator 1. INTRODUCTION Ad-hoc networks are the key factor in the evaluation of wireless communication quoted as corner stones of future generation wireless networking. Wireless LANs support user demand for flawless connectivity, flexibility, and mobility. Generally there are two distinct approaches for enabling wireless mobile units to communicate with each other: Infrastructure-based - Wireless mobile networks have traditionally been based on the cellular concept and relied on good infrastructure support. Infrastructure-less - Infrastructure-less approach, the mobile wireless network is commonly known as a mobile ad hoc network (MANET) i.e. collection of wireless nodes that can dynamically form a network to exchange information without using any preexisting fixed network infrastructure. A fundamental problem in ad hoc networking is routing i.e. how to deliver data packets among MNs efficiently without predetermined topology or centralized control, which is the main objective of ad hoc routing protocols. Since mobile ad hoc networks change their topology frequently, routing in such networks is a challenging task. Moreover, bandwidth, energy and physical security are limited. The Mobile Ad-Hoc Network is characterized by energy constrained nodes, bandwidth constrained links and dynamic topology. Potential applications for this class of network includes instant network infrastructure to support collaborative computing in temporary or mobile environments, emergency rescue networks for disaster management, remote control of electrical appliance, communication systems such as IVC (Inter-Vehicle Communications), and mobile access to the global Internet. Routing protocols for Ad-hoc networking can be classified into four categories viz. (i) Based on routing information update routing mechanism (proactive or table- driven, reactive or on-demand and hybrid protocols), (ii) Based on the use of Temporal information (Past Temporal and Future Temporal) for routing, (iii) Based on routing topology (Flat Topology, Hierarchical Topology), (iv) Based on the Utilization of Specific Resources (Power Aware Routing and Geographical Information Assisted Routing) [29]. 1.1. DESTINATION-SEQUENCED DISTANCE-VECTOR ROUTING [DSDV] [6]: The Table-driven DSDV is a proactive protocol that is modified version of the Distributed Bellman-Ford (DBF) Algorithm that was used successfully in many dynamic packet switched networks The design goals of DSDV were to keep the simplicity of the distributed Bellmann –Ford and to avoid the looping problem in routing tables using the concept of sequence number. It uses full dump and update increment to lessen the traffic load. The improvement made in this is the avoidance of infinite loop. In DSDV, each node is required to transmit a sequence number that is linked to destination usually originated by owner ,at which is periodically increased by two and transmitted along with any other routing update messages to all neighboring nodes .A non-owner node updates a sequence number of a route is when it detects a link break on that route. Owner nodes uses even numbers and non owner nodes uses odd numbers as sequence number. 1.2.DYNAMIC SOURCE ROUTING PROTOCOL (DSR) [7]: The Dynamic Source Routing (DSR) protocol is an on- demand reactive unicast routing protocol based on source routing. DSR protocol is composed by two “on-demand” mechanisms, which are requested only when two nodes want to communicate with each other. In DSR, each node uses buffer technology to keep route information of all the nodes. There are two major phases in DSR such as:  Route discovery  Route maintenance In DSR, every mobile node in the network needs to maintain a route cache where it caches source routes that it has learned. When a host wants to send a packet to some other host, it first checks its route cache for a source route to the destination. In the case a route is found, the sender uses this route to propagate the packet. Otherwise the source node initiates the route discovery process. Route discovery and route maintenance are the two major parts of the DSR protocol. 1.3.TEMPORALLY ORDERED ROUTING ALGORITHM (TORA): TORA (Temporally ordered Routing Algorithm) is an on-demand distributed routing protocol which uses a reversal algorithm and designed for route initiated by source nodes or rather, on demand and provide loop free and multiple routes(to lessen congestion) and it establish route quickly and minimize the overhead while communication Kuljit Kaur et al, / (IJCSIT) International Journal of Computer Science and Information Technologies, Vol. 2 (5) , 2011, 1999-2003 1999