# INTRODUCTION ireless sensor networks are defined as an autonomous, adhocsystem consisting of a collection of networked sensor nodes designed to intercommunicate via wireless radio. Theses are of small with sensing, computations, and wireless networking capabilities, and as such these networks represent the convergence of important technologies. Sensor networks have enormous potential for both consumer and military applications. Military mission require sensor and other intelligence gathering mechanisms that can be placed close to their intended targets. the solutions to these constraints lies in large arrays of passive electromagnetic, optical, chemical, and biological sensors [2]. These can be used to identify and track targets, and they serve also as a first line of detection for various types of attacks. Such networks can also support the movement of unmanned robotic vehicles. The design considerations for some industrial applications are quite similar to those for military applications. Most sensors will be deployed with non-rechargeable batteries. The problem of battery life time in such sensors may be surrounded by using ultra small energy-harvesting radios. Research in this area promises radios smaller than one cubic centimeter, weighing less than 100grams, and with a power dissipation level below 100 microwatts [10]. Sensor networks are very different from conventional computer networks.First, because sensors have a limited supply of energy, energy-conserving forms of communication and computation are essential to wireless sensor networks.Second,since sensors have limited computer power, they may not be able to run sophisticated network protocols.Third,since the bandwidth of wireless link connecting Sensor nodes is often limited,intersensor communication is further constrained. The goal of this paper is to Carry out a systematic performance study of three dynamic routing protocols for WSN,the Dynamic Source Routing protocol(DSR) [5],the Ad-Hoc On-Demand instance Vector protocol(AODV) [6]&DSDV [1] for wireless sensor networks using NS2. # a) NetworkSimulator2 It is Discrete event simulator developed in C++.NS-2[14] is one of the most popular non-specific network simulators, and supports a wide range of protocols in all layers. It uses OTcl[Y]as configuration and script interface.NS-2 is the paradigm of reusability. It provides the most complete support of communication protocol models, among noncommercial packeges.several projects intend to provide WSN support to NS-2 such as Sensor-Sim [5] and NRL [14].Both are extensions of NS-2 to support WSN modeling.NS-2 can comfortably model wired&wireless network topologies up to 1,000 nodes or above with some optimizations. This experiments size can be kept for wireless using some optimizations [11] .A disadvantage of NS-2 is that it provides poor graphical support, via Nam.This application just reproduces a NS-2[12] trace The key motivation behind the design of ondemand protocols is the reduction of the routing load. High routing load usually has a significant performance impact in low bandwidth wireless links. Including this section, this paper has five sections, Section1shows about importance of wireless sensor network Section2 highlights sensor's simulation model.Section3 describes how protocols mechanisms are simulated and enlists simulation model parameters.Section4 discusses results which are obtained from various cases. Finally in section5 analysis on the basis of results is given. # II. # SIMULATION MODEL The goal of simulation is to simulate and closely model the sensor network scenario [14]. The broad outline of any sensor network can be represented by high-level representation as shown in Fig. 1.The sensor model can be represented by the sensor node model and the power model. The free space propagation model assumes the ideal propagation condition that is only one clear line of sight path between the transmitter and receiver [3]. H.T.Friis presented equational1 to calculate the received signal power in free space at distance from the transmitter Equation .1 : received signal power in free space Pt is the transmitted signal power,Pr is the received signal power,Gt, Gr are the antenna gains of the transmitter and the receiver respectively and L is the system loss d) Implemented Algorithm Explanation This section explains how AODV [8] is simulated; DSR [9]&DSDV [1] algorithms are simulated in the manner except it has a slight difference in maintaining routing information. In AODV, each node maintains two separate counters: 1. Sequence number, a monotonically increasing counter used to maintain freshness information about the reverse route to the source. 2. broadcast-ID, which is incremented whenever the source issues a new route request (RREQ) message. Each node also maintains information about its reachable neighbors with bi-directional connectivity. Whenever a node (router) receives a request to send a message, it checks its routing table to see if a route exists. Each routing table entry consists of the following fields: When a node needs to determine a route to a destination node, it floods the network with a route request (RREQ) message as shown in fig. 2. if a route exists, the originating node sends data packet to destination [9]. Otherwise, it saves the messages in a message queue, and then it initiates a route request to the destination (destination node) it replies with RREP (route reply) message, so that path can be determined/ established by source node and communication can take place. # IV. DIRECT-SECQUENCED DISTANCE VECTOR ROUTING(DSDV) It is table driven routing protocol based on Bellman-Ford Routing Algorithm with certain improvements. Every mobile station maintains a routing table that lists all available destinations, the number of hops to reach the destination and the sequence number assigned by the destination node [1]. The sequence number is used to distinguish stale routes from new ones and thus avoid the formation of loops. The stations periodically transmit their routing tables to their immediate neighbors. A station also transmits its routing table if a significant change has occurred in its table from the last update sent.So,the update is both timedriven and event drive[10]. V. # DYNAMIC SOURCE ROUTING The Dynamic source routing (DSR) is based on source routing, which means that the originator of nodes through which the packet must pass while travelling to the destination. The DSR protocol consists of two basic mechanisms: Route Discovery and Route Maintenance [5] a) RouteDiscovery Route discovery is used only when a source node attempts to send a packet to a destination node and does already know a route to it[10] To initiate the Route Discovery, the source node transmits a "Route Request "with a unique ID as a single local broad cast packet. when some intermediate node receives this Route Request, at first it determines whether it has seen the Route Request or not. If the node has already seen the Route Request earlier, it will discard the packet; otherwise it will check its Route Cache whether there is a route to the destination of the packet [5]. If it has the route to target in its routing cache ,it returns a "Route Reply "to the initiator of the Route Discovery, giving a copy of the accumulated route record from the Route Request; otherwise it transmits the Route Request until the Route Request is received by the target [9] b) Route Maintenance DSR Protocol implements the route maintenance mechanism while communicating the packets from source node to destination node. In this scenario DSR protocols uses the route mechanism, to detect any other possible known route towards the destination to transmit data [8]. If the route maintenance fails to find an alternative known route to establish the communication then it will invoke the route discovery to find the new route to destination. Simulations were run for varying number of packets with constant packet size and the result is plotted in fig. 5. the result shows that the delay of DSR is slightly less than DSDV& AODV for increasing number of packets, the delay is more for DSDV at lower no. of packets According to above result, it can be said that AODV[ outperforms DSR for more number of sources or for more network traffic and DSR performs better even though increasing more number of packets in terms of delay [3]. # b) Packet Delivery Ratio (PDR) Comparison with varying no. of packets The results plotted in fig6 is that delivery ratio is linearly increasing at lesser no. of packets ,PDR decreases at higher no. of packets in the case of DSDV.PDR is constant for all values in the case of AODV.PDR linearly varying at higher no. of loads in DSR [5].AODV outperforms than DSDV&DSR. # CONCLUSION & FUTURE WORK In this paper we simulated wireless sensor networks routing protocols for DSDV, AODV&DSR using PHENOM attributes and comparing the performance analysis of various parameters like Packet Delivery Ratio(PDR),Delay&Drop usingNS-2.26. To enhance these protocols by adopting various routing techniques with the help of OTCL linkage with C++ in order to get Energy Efficient Model. ![Fig1 : Sensor node representations in a networ III.](image-2.png "Fig1:") ![a) Destination address b) next hop address c) Destination sequence number Pr ( * * * 2) / (4 )2* 2* Pt Gt Gr d L ? ? = © 2011 Global Journals Inc. (US) Global Journal of Computer Science and Technology Volume XI Issue XX Version I 54 2011 December Performance Evaluation of Wireless Sensor Network Routing Protocols for Real Time Application Support b) Simulation model Table1 : Node configuration parameters](image-3.png "") ![Fig2 : Propagation of RREQ](image-4.png "Fig2:Fig4:") 5![Fig 5 : Packet-Delay Comparisons](image-5.png "Fig 5 :") © 2011 Global Journals Inc. (US) Global Journal of Computer Science and Technology Volume XI Issue XX Version I December DecemberPerformance Evaluation of Wireless Sensor Network Routing Protocols for Real Time Application Support DecemberPerformance Evaluation of Wireless Sensor Network Routing Protocols for Real Time Application Support * Routing Protocols for Ad Hoc Mobile Wireless Networks PadminiMisra * Wireless Sensor Networks: A survey IFAkyildiz WSu YSankarasubramaniam ECyirci Computer Networks 38 4 2002 * Energy Efficient Protocols and Schemes for Wireless SensorNetworks Praveen Namboori, Department of Computer Science, North Dakota State University * Wireless mesh networks: a survey IanFAkyildiz XudongWang WeilinWang * The Dynamic Source Protocol for Ad hoc Networks JBroch DJohnson DMaltz Oct.1999 * Ad-hoc On-Demand Distance Vector(AODV)Routing CharlesEPerkins ElizabethMBelding-Royer And IanDChakeres Internet Request for Comment C3561 July2003 * System architecture directions for networked sensors JHill RSzewczyk AWoo SHollar DCuller KPister Proc.APSLOS-IX .APSLOS-IXNovber 2000 * CharlesEPerkins ElizabethMBelding Royer SamirRDas AdHoc On-demand Distance Vector (AODV) Routing July 2000 * Study of DSR Routing Protocol in Mobile Adhoc Network SangeethaBiswal International