Saturday, March 30, 2019
Mobile Ad Hoc Networks MANET
Mobile Ad Hoc lucres MANET generalizationMobile Ad Hoc Net guide (MANET) is a receiving set receiver net achievement satisfactory of autonomous operation. MANET spread-eagleing has no refractory base beam and whence lymph glands in the cyberspace argon unsettled and self configuring. A MANET is characterized by multi skips routing so that knobs be non machine-accessible to layer 2 just potty pass around by means of with(p) layer 3 routing. In MANET e rattling thickening is a authority channelr and the topologies argon dynamic due to client mobility. This paper shows a panoptic battleground of four MANET routing converses communications communications communications protocols ADOV (Ad Hoc On be pay heedch Distance Vector), DSR ( energising bug Routing), OLSR (Optimized touch State Routing) and TORA (Tempor exclusively(a)(prenominal)y Ordered Routing Algorithm). For testal blueprint six scenarios arrive at been considered. These 6 scenarios argon ge ne footstepd with 3 diametric avocation parameters namely high issue video, light HTTP and high FTP load. This art was passed individu solelyy on to sever completelyy scenario on 2 dissentent customer setup (20, 100 leaf customers). Fin anyy, graphical evaluation of some(prenominal)ly protocol was found on their achievements which argon metric on the basis of mathematical fulfill inflection apply which ar culmination to final stage cargo hold, Ne 2rk load and Throughput.Chapter 1 entranceThis chapter demonstrates a drawing all overview of the bulge. Now sidereal days in our day to day life we put through with(predicate) so m apiece changes around the serviceman accelerating with respect to technology. In this expert world net in stick has brought revolution in colloquy media. Communication is verbalize to the method of entropy win over two mingled with ii tribe or amidst two supplant examplers (in equipment casualty of computers) . Communication is verbalize to be do when a charge up or a cognitive content is passed over the spiritualist among two people. hither the usage of internet comes into existence. Internet enti intrustt joint be employ as sh atomic descend 18d medium for training interchange betwixt manipulationrs around the globe. This cultivation locoweed be of any caseShort Message military postFile sendsVideo speech sound etcWhen these tokens of knowledge atomic cast 18 passed among internet, it uses either the pumped-up(a) media (for connecting users locally) or wire slight media (for connecting locally or globally). When this development exchange is d wiz the parcels carry that knowledge through the protocols accessible for the respective media to put up the bundle to the end bear down. This is the process of information exchange. In this paper, similar exit is experimented over MANET (Mobile Ad Hoc Net bends) chapter 2 for information exchange development four dif ferent protocols. This setup was d hotshot internally over a virtual setup of net profits employ OPNET puzzleler 14.5. So the investigation of protocols is d unitary establish on the functioning of apiece protocol. In the scenarios, separately protocol is passed with 3 different types of vocations namely tall FTP load, High annunciation Video and Light HTTP Browsing. This thesis concludes the performance of four routing protocols towards through the end.Keywords MANET, AODV, OLSR, TORA, DSR, OPNET modeler 14.5.1.1 Organisation of ThesisThis thesis gives an overview of how the image is organised with respect to each chapter. The very first chapter is Introduction of the Thesis, which shows a project idea and the tasks to get through the goals. Second chapter Literature Survey which contains the studies and gain which has been d cardinal previously by oppo presente authors on the link to topics with the parameters employ by them for their treat. The scenarios apply for my work argon related more or littlewhere by overall different directs ar interpreted with different parameters utilize. Again the smorgasbord and the background work of MANETs be explained fol low-downing the comparison of MANET routing protocols. The parameters and scenarios utilize for my work argon explained briefly with the theoretical ac opine setup in chapter 3, Implementation. The results of the semblances and experiments per organize be explained in chapter 4, Performance military rank and Design. The results atomic repress 18 inducen graphically which armed dish outs in comparing the results for routing protocols once against the performance metrics apply to investigate the performance. The graphs be explained briefly in chapter 4. The results ga in that respectd with the help of scenarios in chapter 3 argon concluded with the future(a) work on the routing protocols in chapter 5, Conclusion and Future Work. Finally the support documents for the pr oject which helped in do the theoretical account and project start up is kept in vermiform process A. And finally chapter 6 shows all the fountains and references used for the thesis to help in achieving all the supported information and work.1.2 accusatory of WorkThe main objective of this work is to study the different routing protocols, which be developed for Mobile Ad hoc profitss (MANETs), and to comp atomic number 18 the different routing protocols by employ excuse tool OPNET modeler 14.5. As a part of the work four major routing protocols OLSR, AODV, DSR and TORA gravel been considered and carried out the mannequins for comparing the performance of these protocols. lead performance metrics clutch Network Load and Throughput argon used to comp be the performance of the routing protocols.intention 1To get a blow over concord and functioning of different routing protocols for Mobile Ad hoc interlocks. This objective could be achieved by reading and understand ing the various papers on tap(predicate) on routing protocols of Mobile Ad hoc nets. bearing 2To do a belles-lettres survey of previous work accommodate on MANET Routing Protocols so that something different and efficient show could be introduced. For this objective different articles and papers published has been analyze thoroughly and analysed from websites, books and all relevant re bloodlines available. By going through literature survey on routing protocols, the desired simulation surround and setup pretend been introduced with different simulation parameters. Literature Survey is explained in chapter 2. accusive 3Conducting an experiment and collecting the outturn infoThis objective has been achieved by designing the allow for meshworks with the appropriate simulation parameters and running a simulation for different protocols for different performance metrics. After conducting the simulation the output information have been collected graphically. The results be shown graphically and explained in the project in chapter 4.Objective 4Analyzing the output info and ending up with abridgment and the conclusionThe results have been studied and explained in chapter 4. After studying the simulation results conclusion has been make with some future work which dejection be through further. Conclusion of the project and future work is explained in chapter 5.Chapter 2 Literature Survey2.1 IntroductionThis chapter gives a brief introduction just or so the work d iodin in previous related papers and reports related to this project. In addition, the introduction to the routing protocols and their motley with respect to routing is demonstrated. This chapter is a short polish of the previous work d wiz and the excess objectives regarding routing protocols. The four MANET routing protocols atomic number 18 selected to quantify the performances they be OLSR, AODV, DSR and TORA. The further implementations of these protocols atomic number 18 e xplained later in this thesis (Chapter 3). MANET is an stand less web which provides the granting immunity to the lymph glands to be free to move any aim in the communicate (Stefano Basagni, 2004).2.2 middleman up Work on Routing ProtocolsAs we arrest from (Mahmoud), analysis of two re active agent protocols DSR and TORA were d unrivaled using OPNET Modeller. In their simulation scenario, they used 50 tuner devices in each scenario with constant traffic parameters and protocol specification settings. They have passed FTP traffic of 1000 bytes do it constant throughout the simulation. Evaluation of these protocols was d angiotensin converting enzyme based on the performance metrics used which argon Delay, Data dropped, Throughput and media access delay. Their simulation results shows that DSR performance was break off than TORA in terms of throughput as TORA produces less throughput due to additional operating expense used for caterpillar track creation and thorough outlying(prenominal)e maintenance. At the akin time TORA minimizes communicating bash by localization which results in less delay when comp atomic number 18d to DSR as in that respect is no such mechanism in DSR.Similarly, from (Zukarnain, 2009) they have done evaluation of MANET routing protocol AODV in golf club to try out the connection between the bosss since the quick client ass change their analysis situs frequently. So their study was carried on different busy node heading pattern which are random Way collect Mobility Model, stochastic Walk Mobility Model and stochastic Direction Mobility Model. In order to evaluate the performance of the protocol with these node movement patterns, performance metrics used were Routing budget items, Throughput and software package manner of speaking ratio. They used 2 simulation scenarios where in the first scenario comparison was made on different mobility model varying different act of nodes 5, 10, 15, 20, 25 with r efractory speed of 15m/s and in some a nonher(prenominal) case comparison was made to evaluate the protocol on different mobility models with varying speeds 5, 10, 15, 20 m/s and 50 nodes as constant all through. They concluded that stochastic waypoint model is outmatch for AODV compared to other mobility models as the protocol produces highest throughput than compared to others.Other related work from (Nyirenda, 2009) gives the similar operative(a) of MANET routing protocols AODV, OLSR, DSR and TORA on OPNET 14.5. Their work carried out for study the performance of the four protocols by different performance metrics which are Network load, Packet preservation ratio, Packet end-to-end delay and Throughput. The simulation setup which was implemented on 6 different scenarios where the traffic leaving on to the net was ranging from low to high net load, nodes changing from 5, 20, 50 and with speed ranging from 10 m/s to 28 m/s. Mobility model used in this was Random waypoint model for mobility pattern. They conclusions included in their work showed that OLSR performed better compared to the other protocols as it has a bad routing crash and hence it is comfortably suited for ample and complex mesh topologys. So apart from routing overhead OLSR performed better but with routing overhead DSR is better. just when in small vane AODV is oft better compared to other protocols. So finally, proactive protocols perform substantially in high energy ties whereas reactive protocols perform better in low potentiality communicates.From a nonher(prenominal) paper (Maltz, 2001), we see that working on demand routing protocols in MANET was done where DSR protocol was compared to other on demand protocols like AODV, TORA and DSDV. semblance setup carried is represented in add-ins underWith the to a higher place simulation setup the protocols were evaluated based on the performance metrics used which was Packet delivery ratio, Routing overhead, Path optima lity and lower speed of nodes. The conclusions showed that DSR performed well when referred to piece of land loss rate and routing over head is concerned. Of all awake implementation done with all the above parameters tested on the experiment test beds DSR out performed in every case scenario used when compared all the other protocols used in this setup.2.3 Background WorkA network outhouse be give tongue to as association of different systems or organizations where sharing the information stub be done collectively. Whereas in rationalness terms it butt be merely defined as a group of computers connected unneurotic logically to share information like printing, faxing, and so forthThe network so-and-so be divided into 2 types based on their working behaviour. They are base network These networks are used where the topology is said to be restrict and on that point is a fixed point like base invest ( broadly referred as despatchr) to transmit signals and the end points which are connected to base put up drop dead with each other devices on the network switching from one base station to another. When a node moves out of range in spite of appearance its network, then it is said to be connected to another base station range where this process is referred as hand dark. We weed often see this type of mechanisms in infrastructure and fixed or pumped(p) networks.Infrastructure less network These networks are a classifiable type of networks where in that location are no such fixed nodes or topologies on the network and the end pints or devices on the network are free to communicate with each other devices on the network as each device on the network behave themselves as way of lifers and encourages chat process all over the network. By this we can say that tuner technology is a assure technology that can tolerate the information exchange worldwide. In the determination decade we can to a fault see the constant increase in the growth wireless technology issues, one of which being meandering(a) devices such as laptops, cell phones, PDAs etc Ad hoc networks are too the part of this type of network.Mobile Ad hoc network is a bran- naked as a jaybird technology emerged with the venture of wireless networks. These networks are very natural and do not use any fixed infrastructure for communicating process. The nodes connected in these networks are wireless links which are mobile in nature and communicate with each other mobile node in the network with wireless transmission and topology is said to base by the intermediate nodes on the network which are helpful for converse process. As there are no fixed infrastructure and bound topology constraints the nodes on the network are free to join and contribute the network and this is feasible as the nodes on the network are mobile. due to this random movement of the nodes in the network the topology of the network changes dynamically. out-of-pocket to this change protoco l moldiness be able to acclimatize with these movements and are withal responsible to produce the bridle- cartroads of the information travelled without disturbing network connectivity.This excogitation of ad hoc network allows each node on its network to act like bridle- thoroughfarer, resulting in the flow of information exchange with multi skip routing. These types of networks are widely used in military and other give up applications. (Saadawi, 2003)2.4 RoutingRouting is the process of moving the information from one place of the network to another. The one end should be the root system which intends to transfer the data to the end (other end). The concept of routing has been there since seventies but it has caught the move in 1980s. In 1970s networks were simple and today there are large scale networks in existence. To move the data from one armament to another at to the lowest degree one thoroughfarer is required in the network. laner has all the information rega rding militarys in the network and it can manipulate the outstrip(p) affirmable route as well. (Javvin, 2004)Routing takes place at Layer 3 in OSI 7 layer Model. just to the highest degree of the protocols at layer 3 are IP and IS-IS. These protocols carry the data between start and finish along with their regalees in the data parcel. Routing involves two basic activities Path stopping point and Switching. These two activities are capable to encounter the optical routing way and to transfer the data parcels through internetworking. This is called Switching. Switching can still be slatternly where as determining the reliable path is difficult.Path DeterminationRouting depict use of the different routing protocols to specificize the best possible path to deliver the data. Routing protocols use the metric to calculate which the best possible path to run the task is. The metric used could be path bandwidth, path length, delay etc. to determine the optimal path. To det ermine the path in the network, routing algorithms pleads the routing tables which are used to store the routing information about the network. travel guidebookrs communicate with each other in order to accommodate back their routing tables which make communication easier and faster. Routing information can vary according to the routing algorithm used for the process. (Cisco, 2010)SwitchingApart from path determination, router shows one more activity Packet Switching. Switching simply performer send oning the required data from one embrasure to the another in order to reach the coating. In this case, the data to be forwarded is packet. The spare-time activity(a) interface utter is decided by using the refinement sell present in the packet. Though the nodes know the adjoining hop cry, they still occupy to know how to use it. So for that tenability they use routing tables. The routing table throws the packet away when the terminal figure is unknow. But when the desti nation is known routing table posses all the interface information forming the route to the destination. (2006)The coterminous hop address could be another swarm or either it could be a router. fit in to ISO developed hierarchical terminology, the systems which have the strength to forward the data from the source to the destination are called median(a) Systems (IS) and the systems which fails to do so are called as End systems (ES). When it is a router it follows the selfsame(prenominal) military operation as this one, and if it is a host it simply forwards the packet. In packet switching, the Layer 3 address of the source and the destination remains the same to authenticate the original vector and the receiver. However the Layer 2 address (MAC) changes from router to router and from router to host which at dwell determines the destination host. (Cisco, 2010)2.5 Ad hoc NetworksAn ad hoc network is a collection of umteen autonomous nodes connected together by radio waves and introduce the connectivity in de cardinalised manner. wireless ad hoc networks are connected through wireless links so there is no contract of any animal(prenominal) medium and hence contend of the medium is always there such as noise, interference and fading. On ad hoc networks each node functions as a node and a router itself. It simply factor there is no take of an additional switch or a router to route the data and the work is given to the nodes themselves. (Yang Li, 2010)2.6 Mobile Ad hoc NetworksA Mobile Ad hoc Network is an autonomous network formed by hundreds or thousands of nodes. These networks dont need any infrastructure as they can act as a node and router itself. They are free to move anywhere in the network and are connected through radio links. The wholly limitation with the MANETs is that they can communicate in a particular rage of the radio waves and outside(a) the network they need some additional arrangements to communicate. To overcome this limit ation the Intermediate Node or sometimes called as Relays are brought into picture. Intermediate nodes help in forwarding the packets to the destination. In MANET nodes are free to travel anywhere in the network, hence network topology cannot be fixed for such networks and it harbors changing depending on the current office of the nodes. (ANTDS, 2001)The fundamental differences between the wired networks and MANET areAsymmetric Links extra LinkInterference self-propelling network topology2.7 Characteristics of MANETsThere are several MANET routing protocols which should handle the several innate characteristics of MANETs as follows as mentioned in (Subbarao)(Jain, 2005)Dynamic Topologies Since the MANET is infrastructure less ad hoc networks, the nodes are free to move arbitrarily. The mobility of nodes whitethorn be random and so unpredictable. So the links between the nodes whitethorn be unidirectional or bidirectional at times.Bandwidth Constrained, Variable efficacy Wirele ss Links Wireless links generally are bandwidth constrained. Since there is a lower electrical capacity in wireless links as compared to the wired links, the traffic over-crowding is typical rather than different. button/ advocate Constrained Operation Energy consumption is vital in MANETs as these nodes operate typically off power limited sources. Some or all nodes in MANETs bank on batteries.Limited Physical earnest Wireless networks like MANETs are more vulnerable with the security issues available with them. Issues like eavesdropping, jammer attack, spoofing and denial of service attacks must be carefully considered.2.8 desire of MANET Routing ProtocolsA mobile ad hoc routing protocol is used to discover unseasoned routes and corroborate the existing routes between the nodes in the network. MANET (Mobile Ad Hoc Network) is the collecting of mobile nodes which are present in random manner in the network has the capacity to communicate and exchange information rough-and-re adyly over the network by facilitating the intermediate nodes for their communication. The indispensable task of a MANET protocol is to build or discover the countervail and efficient routes between the nodes so that information can be delivered accurately with respect to time. avenue construction should be done with less overhead and minimal bandwidth consumption for effective communication.2.9 Applications of MANETsApplications of MANETs can be used in many critical situations today and are increasing widely. There are many applications of MANETs today and some of them are mentioned here. An ideal application is for look to and rescue trading operations. Such kind of operations is characterized by the networks without having an infrastructure present. atomic reduce 53 of the reasons for this may be because all of the equipment was done for(p) or may be the region is too remote. Rescuer must be capable of communicating to use their energy fairly and also they must maintain the security. Carrying the equipments for communication that the rescuers are already using makes the undertaking easier.The commercial application for MANETs includes calculate everywhere which means the mobile devices are free to move anywhere in the network and yet it is possible to be in communication with the devices. The computers are allowed to forward the data to another computer or data networks may be extended far beyond the considered reach. Such networks may be more widely available and much easier in use. some other important application of MANETs is sensing element Networks. Sensor networks are composed of very large number of small sensors which are able to detect number of properties of the surface area, for example temperature, pressure, toxins, pollutions etc. In this case, the electrical capacity of sensor network is much limited. So there is always need to forward data to the central computer and for this purpose they have to rely upon others in order to f orward data to the central computer. The sensor networks each are limited in their computing capabilities but together can be very effective and the key to future homeland security. But individual sensors because of their limited computing capabilities can analyse prone to nonstarter and loss.There are many other applications of MANETs like personal area networking where the communicating nodes may be mobile phones, laptops etc. Also this has a potential in military operations with the nodes of the network as soldiers, tanks and airplanes. some more areas includes civilian environment to diverse taxi cab networks, assembly rooms, boats and ships. (Bluetronix, 2006)2.10 Classification of Routing ProtocolsAccording to (Jain, 2005), ad hoc routing protocols can be classified mainly into two categoriesTable driven (proactive) Routing2.10.1 Proactive (Table-Driven) Routing ProtocolsThese routing protocols are similar to and come as a born(p) extension of those for the wired netwo rks. In proactive routing, each node has one or more tables that contain the in style(p) information of the routes to any node in the network. Each row has the next hop for reaching a node/subnet and the cost of this route. Various table-driven protocols differ in the way the information about a change in topology is propagated through all nodes in the network. (LinuxOnly)In proactive routing protocol each node maintains the up to date routing information of all nodes in the network. Here each node maintains the routing table and broadcast it when there is a change in network topology. As soon as source needs the route to the destination it can select from the routing table. The routing table is transfer periodically by publicize to all nodes in the network to keep track of the new pith even though the topology is not changed. Each nodes has the routing information of all nodes in the network though most of it undesired. Advantages of proactive protocols are that the communicati on experiences a minimal delay and routes are up to date. Disadvantage is that the routes are broken as a result of mobility of nodes. (Chang)Following are the examples of table driven protocols GSR and OLSR and some other proactive routing protocols are FSR, HSR, ZHLSR, CGSR and WRP etc.2.10.1.1 OLSR (Optimized Link State Routing)OLSR Protocol is based on traditional link put up algorithm which supports point to point routing strategy. In this strategy the nodes keeps exchanging the information periodically in order to maintain the network topology within the network. OLSR is an optimization version of link state protocols. That means it keeps flooding the topological changes information to all the hosts crosswise the network when happens. OLSR is also proved beneficial for the reason that it minimizes the size of each consider nitty-gritty exchanged and also it avoids each node to rebroadcast during the updating of the routes. It uses the Multi register Re bring ining (MPR) st rategy to do the above task. For MPR strategy each node creates a set of all of its neighbouring nodes, generally called multipoint relays of the node, in the network to transmit the packet once again. Each node in the particular set can receive and process the packet but further cannot retransmit it. To use MRPs, each node has to keep broadcasting periodically to all one hop neighbours using how-do-you-do piths. Another method to reduce the overhead is to provide the shortest path. When the time detachment is reduced for the control heart and souls transmission, it can prove more reactive to the topological changes (Kuosmanen).The implementation of OLSR protocol basically uses two control meanings Hello nub and analysis situs Control (TC). The hello centers are to be sent solely one hop away from the host and are used for finding the link state information and hosts neighbours. MPR chooser sets are constructed with Hello messages which explain which host in the network ha s chosen this host to act as MPR and using the information the host can select its own set of MPRs. The Topology control (TC) messages are to be broadcasted across entire network about the advertised neighbours and it includes at least the MPR picker list. As OLSR is proactive preliminary and it keeps updating the routing table periodically, the TC messages are also broadcasted periodically and the hosts with MPR selector set can only forward the TC messages.There can also be MID message which is Multiple Interface resoluteness message to declare that the announcing hosts can have multiple OLSR interface addresses. And again MID message are broadcasted throughout entire network and only by MPRs.2.10.2 Reactive (Source Initiated) Routing ProtocolsThese protocols take a lazy approach to routing. They do not maintain or evermore update their route tables with the modish route topology. Reactive routing is also known as on-demand routing. The Reactive Routing Protocols are also cal led as Source initiated look at Driven protocols. They are called so because the routes are discovered only when indispensable by source.Source initiated on demand networks cerates routing only when desired by the source node. When source wants to communicate with destination then it invokes the route discovery mechanism to find the path to the destination. The route discovery process is spotless once a route is found or all possible are identified. Once the rout is formed between source and destination it is maintained by a route maintenance procedure until the destination becomes inaccessible or the route is no longer desired. (Chang)These Examples of reactive routing protocols are dynamic Source Routing (DSR), Ad hoc on-demand distance vector routing AODV, ABR, SSA, CBRP, and RDMAR.2.10.2.1 AODV (Ad hoc On conduct Distance Vector)Ad hoc On Demand Distance Vector protocol as the name implies it is an On Demand that is, Reactive Protocol. AODV is capable of both unicast and mul ticast routing. It is an on demand algorithm, it means that it builds routes between nodes only as desired by source nodes. It uses the concepts of DSR routing for route discovery and route maintenance and DSDV protocol for the concept of rank number. It uses season number concept to ensure the archness of routes. The ad hoc on-demand Distance vector algorithm facilitates the self-starting, multi hop and dynamic routing between participating nodes to establish and maintain an ad hoc network. AODV algorithm enables the nodes to find the routes for new destinations as and when they are ask and the nodes are not required to maintain the routes to the destination that are not in the part of active communication. It also enables the nodes in the formation of multicast groups and enables the nodes to suffice quickly to link breakages and topological changes in the network thus the operation of AODV is spiral free and thus avoids the Balham Ford count to infinity problem.AODV routing protocol is a simple and effective routing protocol for Ad hoc networks. It also uses the concept of hop by hope routing and chronological succession numbers game from DSDV protocol.The following are the message types defined by AODV they areRoute request (RREQ),Route replies (RREP),Route error (RERR) and group hellos (GRPH) this message types are handled by UDP and IP header.The route request message format contains the following fieldSource address the address of the node which originates the route requestSource range number the current sequence number to be used in deciding the route for the source request terminal address the address of the mark node for which the route is initialized. finishing Sequence numbers the sequence number received by source for route towards the destination.Broadcast ID The sequence number by which a RREQ route request can be unequivocally identified.Hop counts the number of the hops to be taken from the source node to reach the destination node th at handles the Route request.The Route Reply message format contains the following fieldsDestination address the address of the destination node for which the route is aboundedDestination sequence number the destination sequence number related to the routeSource address the address of the source node that originates the route request biography the time for which nodes receiving the route rejoinder considers the route to be valid.Hop counts the number of hops to be taken from source to destination.The route error message format contains the following fieldsUnreachable destination address The address of the destination that has become unreachable due to link failure. (Arbia, 2008)In AODV the only nodes that take active interest in routing process are the nodes that sit in direct path between source and destination. The nodes which do not lie on active path do not take participate or maintain the routing table, thus AODV minimize the number of control messages sent between two nodes . As long as there is a valid routes between the source and destination for communication, AODV does not play any role and when a new route to a new destination is required and if the route to the destination does not exist only then the source node initialize the route discovery process by broadcasting the RREQ message to find the route to destination. TheMobile Ad Hoc Networks MANETMobile Ad Hoc Networks MANETAbstractMobile Ad Hoc Network (MANET) is a wireless network capable of autonomous operation. MANET routing has no fixed base station and hence nodes in the network are mobile and self configuring. A MANET is characterized by multi hop routing so that nodes are not connected to layer 2 but can communicate through layer 3 routing. In MANET every node is a potential router and the topologies are dynamic due to node mobility. This paper presents a comprehensive study of four MANET routing protocols ADOV (Ad Hoc On demand Distance Vector), DSR (Dynamic Source Routing), OLSR (Optim ized Link State Routing) and TORA (Temporally Ordered Routing Algorithm). For experimental purpose six scenarios have been considered. These 6 scenarios are generated with 3 different traffic parameters namely high resolution video, light HTTP and high FTP load. This traffic was passed individually on to each scenario on 2 different node setup (20, 100 nodes). Finally, graphical evaluation of each protocol was based on their performances which are calculated on the basis of performance metrics used which are End to end delay, Network load and Throughput.Chapter 1 IntroductionThis chapter demonstrates a brief overview of the project. Now days in our day to day life we see so many changes around the world accelerating with respect to technology. In this technical world Internet has brought revolution in communication media. Communication is said to the method of information exchange either between two people or between two end users (in terms of computers). Communication is said to be done when a file or a message is passed over the medium among two people. Here the usage of internet comes into existence. Internet can be used as shared medium for information interchange between users around the globe. This information can be of any typeShort MessageMailFile transfersVideoAudio etcWhen these types of information are passed among internet, it uses either the wired media (for connecting users locally) or wireless media (for connecting locally or globally). When this information exchange is done the packets carry that information through the protocols available for the respective media to deliver the packet to the destination. This is the process of information exchange. In this paper, similar work is experimented over MANET (Mobile Ad Hoc Networks) chapter 2 for information exchange using four different protocols. This setup was done internally over a virtual setup of networks using OPNET modeller 14.5. So the investigation of protocols is done based on the perform ance of each protocol. In the scenarios, each protocol is passed with 3 different types of traffics namely High FTP load, High Resolution Video and Light HTTP Browsing. This thesis concludes the performance of four routing protocols towards through the end.Keywords MANET, AODV, OLSR, TORA, DSR, OPNET Modeler 14.5.1.1 Organisation of ThesisThis thesis gives an overview of how the project is organised with respect to each chapter. The very first chapter is Introduction of the Thesis, which shows a project idea and the tasks to achieve the goals. Second chapter Literature Survey which contains the studies and work which has been done previously by other authors on the related topics with the parameters used by them for their work. The scenarios used for my work are related somewhere by overall different results are taken with different parameters used. Again the classification and the background work of MANETs are explained following the comparison of MANET routing protocols. The param eters and scenarios used for my work are explained briefly with the simulation setup in chapter 3, Implementation. The results of the simulations and experiments performed are explained in chapter 4, Performance Evaluation and Design. The results are taken graphically which helps in comparing the results for routing protocols against the performance metrics used to investigate the performance. The graphs are explained briefly in chapter 4. The results gathered with the help of scenarios in chapter 3 are concluded with the future work on the routing protocols in chapter 5, Conclusion and Future Work. Finally the supported documents for the project which helped in making the simulation and project start up is kept in Appendix A. And finally chapter 6 shows all the sources and references used for the thesis to help in achieving all the supported information and work.1.2 Objective of WorkThe main objective of this work is to study the different routing protocols, which are developed for Mobile Ad hoc networks (MANETs), and to compare the different routing protocols by using simulation tool OPNET Modeler 14.5. As a part of the work four major routing protocols OLSR, AODV, DSR and TORA have been selected and carried out the simulations for comparing the performance of these protocols. Three performance metrics delay Network Load and Throughput are used to compare the performance of the routing protocols.Objective 1To get a clear understanding and functioning of different routing protocols for Mobile Ad hoc networks. This objective could be achieved by reading and understanding the various papers available on routing protocols of Mobile Ad hoc networks.Objective 2To do a literature survey of previous work done on MANET Routing Protocols so that something different and efficient simulation could be introduced. For this objective different articles and papers published has been studied thoroughly and analysed from websites, books and all relevant resources available. B y going through literature survey on routing protocols, the desired simulation environment and setup have been introduced with different simulation parameters. Literature Survey is explained in chapter 2.Objective 3Conducting an experiment and collecting the output dataThis objective has been achieved by designing the appropriate networks with the appropriate simulation parameters and running a simulation for different protocols for different performance metrics. After conducting the simulation the output data have been collected graphically. The results are shown graphically and explained in the project in chapter 4.Objective 4Analyzing the output data and ending up with summary and the conclusionThe results have been studied and explained in chapter 4. After studying the simulation results conclusion has been made with some future work which can be done further. Conclusion of the project and future work is explained in chapter 5.Chapter 2 Literature Survey2.1 IntroductionThis chap ter gives a brief introduction about the work done in previous related papers and reports related to this project. In addition, the introduction to the routing protocols and their classification with respect to routing is demonstrated. This chapter is a short review of the previous work done and the additional objectives regarding routing protocols. The four MANET routing protocols are selected to evaluate the performances they are OLSR, AODV, DSR and TORA. The further implementations of these protocols are explained later in this thesis (Chapter 3). MANET is an infrastructure less network which provides the freedom to the nodes to be free to move anywhere in the network (Stefano Basagni, 2004).2.2 Related Work on Routing ProtocolsAs we see from (Mahmoud), analysis of two reactive protocols DSR and TORA were done using OPNET Modeller. In their simulation scenario, they used 50 wireless devices in each scenario with constant traffic parameters and protocol specification settings. The y have passed FTP traffic of 1000 bytes making it constant throughout the simulation. Evaluation of these protocols was done based on the performance metrics used which are Delay, Data dropped, Throughput and media access delay. Their simulation results shows that DSR performance was better than TORA in terms of throughput as TORA produces less throughput due to additional overhead used for path creation and path maintenance. At the same time TORA minimizes communication overhead by localization which results in less delay when compared to DSR as there is no such mechanism in DSR.Similarly, from (Zukarnain, 2009) they have done evaluation of MANET routing protocol AODV in order to establish the connection between the nodes since the mobile node can change their topology frequently. So their study was carried on different mobile node movement pattern which are Random Waypoint Mobility Model, Random Walk Mobility Model and Random Direction Mobility Model. In order to evaluate the perf ormance of the protocol with these node movement patterns, performance metrics used were Routing overhead, Throughput and Packet delivery ratio. They used 2 simulation scenarios where in the first scenario comparison was made on different mobility model varying different number of nodes 5, 10, 15, 20, 25 with fixed speed of 15m/s and in other case comparison was made to evaluate the protocol on different mobility models with varying speeds 5, 10, 15, 20 m/s and 50 nodes as constant all through. They concluded that Random waypoint model is best for AODV compared to other mobility models as the protocol produces highest throughput than compared to others.Other related work from (Nyirenda, 2009) gives the similar working of MANET routing protocols AODV, OLSR, DSR and TORA on OPNET 14.5. Their work carried out for study the performance of the four protocols by different performance metrics which are Network load, Packet delivery ratio, Packet end-to-end delay and Throughput. The simulat ion setup which was implemented on 6 different scenarios where the traffic passing on to the network was ranging from low to high network load, nodes changing from 5, 20, 50 and with speed ranging from 10 m/s to 28 m/s. Mobility model used in this was Random waypoint model for mobility pattern. They conclusions included in their work showed that OLSR performed better compared to the other protocols as it has a bad routing overhead and hence it is well suited for large and complex networks. So apart from routing overhead OLSR performed better but with routing overhead DSR is better. But when in small network AODV is much better compared to other protocols. So finally, proactive protocols perform well in high capacity links whereas reactive protocols perform better in low capacity networks.From another paper (Maltz, 2001), we see that working on demand routing protocols in MANET was done where DSR protocol was compared to other on demand protocols like AODV, TORA and DSDV. Simulation setup carried is represented in tables belowWith the above simulation setup the protocols were evaluated based on the performance metrics used which was Packet delivery ratio, Routing overhead, Path optimality and lower speed of nodes. The conclusions showed that DSR performed well when referred to packet loss rate and routing over head is concerned. Of all careful implementation done with all the above parameters tested on the experiment test beds DSR out performed in every case scenario used when compared all the other protocols used in this setup.2.3 Background WorkA network can be said as association of different systems or organizations where sharing the information can be done collectively. Whereas in computing terms it can be simply defined as a group of computers connected together logically to share information like printing, faxing, etc The network can be divided into 2 types based on their working behaviour. They areInfrastructure network These networks are used where the topology is said to be limited and there is a fixed point like base station (generally referred as router) to transmit signals and the end points which are connected to base station communicate with each other devices on the network switching from one base station to another. When a node moves out of range within its network, then it is said to be connected to another base station range where this process is referred as handoff. We can often see this type of mechanisms in infrastructure and fixed or wired networks.Infrastructure less network These networks are a typical type of networks where there are no such fixed nodes or topologies on the network and the end pints or devices on the network are free to communicate with each other devices on the network as each device on the network behave themselves as routers and encourages communication process all over the network. By this we can say that wireless technology is a promising technology that can tolerate the information exchange worldwide. In the last decade we can also see the constant increase in the growth wireless technology issues, one of which being mobile devices such as laptops, cell phones, PDAs etc Ad hoc networks are also the part of this type of network.Mobile Ad hoc network is a new technology emerged with the hypothesis of wireless networks. These networks are very typical and do not use any fixed infrastructure for communication process. The nodes connected in these networks are wireless links which are mobile in nature and communicate with each other mobile node in the network with radio transmission and topology is said to establish by the intermediate nodes on the network which are helpful for communication process. As there are no fixed infrastructure and limited topology constraints the nodes on the network are free to join and leave the network and this is possible as the nodes on the network are mobile. Due to this random movement of the nodes in the network the topology of the networ k changes dynamically. Due to this change protocol must be able to acclimatize with these movements and are also responsible to maintain the routes of the information travelled without disturbing network connectivity.This concept of ad hoc network allows each node on its network to act like router, resulting in the flow of information exchange with multi hop routing. These types of networks are widely used in military and other rescue applications. (Saadawi, 2003)2.4 RoutingRouting is the process of moving the data from one place of the network to another. The one end should be the source which intends to transfer the data to the destination (other end). The concept of routing has been there since 1970s but it has caught the move in 1980s. In 1970s networks were simple and today there are large scale networks in existence. To move the data from one host to another at least one router is required in the network. Router has all the information regarding hosts in the network and it can manipulate the best possible route as well. (Javvin, 2004)Routing takes place at Layer 3 in OSI 7 layer Model. Some of the protocols at layer 3 are IP and IS-IS. These protocols carry the data between source and destination along with their addresses in the data packet. Routing involves two basic activities Path Determination and Switching. These two activities are capable to determine the optical routing path and to transfer the data packets through internetworking. This is called Switching. Switching can still be easy where as determining the reliable path is difficult.Path DeterminationRouting make use of the different routing protocols to determine the best possible path to deliver the data. Routing protocols use the metric to calculate which the best possible path to accomplish the task is. The metric used could be path bandwidth, path length, delay etc. to determine the optimal path. To determine the path in the network, routing algorithms maintains the routing tables which a re used to store the routing information about the network. Routers communicate with each other in order to maintain their routing tables which make communication easier and faster. Routing information can vary according to the routing algorithm used for the process. (Cisco, 2010)SwitchingApart from path determination, router shows one more activity Packet Switching. Switching simply means forwarding the required data from one interface to the another in order to reach the destination. In this case, the data to be forwarded is packet. The next interface address is decided by using the destination address present in the packet. Though the nodes know the next hop address, they still need to know how to use it. So for that reason they use routing tables. The routing table throws the packet away when the destination is unknown. But when the destination is known routing table posses all the interface information forming the route to the destination. (2006)The next hop address could be an other host or either it could be a router. According to ISO developed hierarchical terminology, the systems which have the capability to forward the data from the source to the destination are called Intermediate Systems (IS) and the systems which fails to do so are called as End systems (ES). When it is a router it follows the same procedure as this one, and if it is a host it simply forwards the packet. In packet switching, the Layer 3 address of the source and the destination remains the same to authenticate the original sender and the receiver. However the Layer 2 address (MAC) changes from router to router and from router to host which at last determines the destination host. (Cisco, 2010)2.5 Ad hoc NetworksAn ad hoc network is a collection of many autonomous nodes connected together by radio waves and maintain the connectivity in decentralised manner. Wireless ad hoc networks are connected through wireless links so there is no need of any physical medium and hence contend of t he medium is always there such as noise, interference and fading. On ad hoc networks each node functions as a node and a router itself. It simply means there is no need of an additional switch or a router to route the data and the control is given to the nodes themselves. (Yang Li, 2010)2.6 Mobile Ad hoc NetworksA Mobile Ad hoc Network is an autonomous network formed by hundreds or thousands of nodes. These networks dont need any infrastructure as they can act as a node and router itself. They are free to move anywhere in the network and are connected through radio links. The only limitation with the MANETs is that they can communicate in a particular rage of the radio waves and outside the network they need some additional arrangements to communicate. To overcome this limitation the Intermediate Node or sometimes called as Relays are brought into picture. Intermediate nodes help in forwarding the packets to the destination. In MANET nodes are free to travel anywhere in the network, hence network topology cannot be fixed for such networks and it keeps changing depending on the current location of the nodes. (ANTDS, 2001)The fundamental differences between the wired networks and MANET areAsymmetric LinksRedundant LinkInterferenceDynamic Topology2.7 Characteristics of MANETsThere are several MANET routing protocols which should handle the several inherent characteristics of MANETs as follows as mentioned in (Subbarao)(Jain, 2005)Dynamic Topologies Since the MANET is infrastructure less ad hoc networks, the nodes are free to move arbitrarily. The mobility of nodes may be random and so unpredictable. So the links between the nodes may be unidirectional or bidirectional at times.Bandwidth Constrained, Variable Capacity Wireless Links Wireless links generally are bandwidth constrained. Since there is a lower capacity in wireless links as compared to the wired links, the traffic congestion is typical rather than different.Energy/Power Constrained Operation Energy con sumption is vital in MANETs as these nodes operate typically off power limited sources. Some or all nodes in MANETs rely on batteries.Limited Physical Security Wireless networks like MANETs are more vulnerable with the security issues available with them. Issues like eavesdropping, jammer attack, spoofing and denial of service attacks must be carefully considered.2.8 Need of MANET Routing ProtocolsA mobile ad hoc routing protocol is used to discover new routes and maintain the existing routes between the nodes in the network. MANET (Mobile Ad Hoc Network) is the collecting of mobile nodes which are present in random manner in the network has the capacity to communicate and exchange information effectively over the network by facilitating the intermediate nodes for their communication. The essential task of a MANET protocol is to create or discover the correct and efficient routes between the nodes so that information can be delivered accurately with respect to time. Route constructi on should be done with less overhead and minimal bandwidth consumption for effective communication.2.9 Applications of MANETsApplications of MANETs can be used in many critical situations today and are increasing widely. There are many applications of MANETs today and some of them are mentioned here. An ideal application is for search and rescue operations. Such kind of operations is characterized by the networks without having an infrastructure present. One of the reasons for this may be because all of the equipment was destroyed or may be the region is too remote. Rescuer must be capable of communicating to use their energy fairly and also they must maintain the security. Carrying the equipments for communication that the rescuers are already using makes the job easier.The commercial application for MANETs includes computing everywhere which means the mobile devices are free to move anywhere in the network and yet it is possible to be in communication with the devices. The compute rs are allowed to forward the data to another computer or data networks may be extended far beyond the considered reach. Such networks may be more widely available and much easier in use.Another important application of MANETs is Sensor Networks. Sensor networks are composed of very large number of small sensors which are able to detect number of properties of the area, for example temperature, pressure, toxins, pollutions etc. In this case, the capability of sensor network is much limited. So there is always need to forward data to the central computer and for this purpose they have to rely upon others in order to forward data to the central computer. The sensor networks individually are limited in their computing capabilities but together can be very effective and the key to future homeland security. But individual sensors because of their limited computing capabilities can prove prone to failure and loss.There are many other applications of MANETs like personal area networking wh ere the communicating nodes may be mobile phones, laptops etc. Also this has a potential in military operations with the nodes of the network as soldiers, tanks and airplanes. Many more areas includes civilian environment to diverse taxi cab networks, conference rooms, boats and ships. (Bluetronix, 2006)2.10 Classification of Routing ProtocolsAccording to (Jain, 2005), ad hoc routing protocols can be classified mainly into two categoriesTable driven (proactive) Routing2.10.1 Proactive (Table-Driven) Routing ProtocolsThese routing protocols are similar to and come as a natural extension of those for the wired networks. In proactive routing, each node has one or more tables that contain the latest information of the routes to any node in the network. Each row has the next hop for reaching a node/subnet and the cost of this route. Various table-driven protocols differ in the way the information about a change in topology is propagated through all nodes in the network. (LinuxOnly)In pro active routing protocol each node maintains the up to date routing information of all nodes in the network. Here each node maintains the routing table and broadcast it when there is a change in network topology. As soon as source needs the route to the destination it can select from the routing table. The routing table is exchanged periodically by broadcasting to all nodes in the network to keep track of the new message even though the topology is not changed. Each nodes has the routing information of all nodes in the network though most of it undesired. Advantages of proactive protocols are that the communication experiences a minimal delay and routes are up to date. Disadvantage is that the routes are broken as a result of mobility of nodes. (Chang)Following are the examples of table driven protocols GSR and OLSR and some other proactive routing protocols are FSR, HSR, ZHLSR, CGSR and WRP etc.2.10.1.1 OLSR (Optimized Link State Routing)OLSR Protocol is based on traditional link st ate algorithm which supports point to point routing strategy. In this strategy the nodes keeps exchanging the information periodically in order to maintain the network topology within the network. OLSR is an optimization version of link state protocols. That means it keeps flooding the topological changes information to all the hosts across the network when happens. OLSR is also proved beneficial for the reason that it minimizes the size of each control message exchanged and also it avoids each node to rebroadcast during the updating of the routes. It uses the Multi Point Replaying (MPR) strategy to do the above task. For MPR strategy each node creates a set of all of its neighbouring nodes, generally called multipoint relays of the node, in the network to transmit the packet once again. Each node in the particular set can receive and process the packet but only cannot retransmit it. To use MRPs, each node has to keep broadcasting periodically to all one hop neighbours using hello m essages. Another method to reduce the overhead is to provide the shortest path. When the time interval is reduced for the control messages transmission, it can prove more reactive to the topological changes (Kuosmanen).The implementation of OLSR protocol basically uses two control messages Hello message and Topology Control (TC). The hello messages are to be sent only one hop away from the host and are used for finding the link state information and hosts neighbours. MPR selector sets are constructed with Hello messages which explain which host in the network has chosen this host to act as MPR and using the information the host can select its own set of MPRs. The Topology control (TC) messages are to be broadcasted across entire network about the advertised neighbours and it includes at least the MPR selector list. As OLSR is proactive approach and it keeps updating the routing table periodically, the TC messages are also broadcasted periodically and the hosts with MPR selector set can only forward the TC messages.There can also be MID message which is Multiple Interface Declaration message to declare that the announcing hosts can have multiple OLSR interface addresses. And again MID message are broadcasted throughout entire network and only by MPRs.2.10.2 Reactive (Source Initiated) Routing ProtocolsThese protocols take a lazy approach to routing. They do not maintain or constantly update their route tables with the latest route topology. Reactive routing is also known as on-demand routing. The Reactive Routing Protocols are also called as Source initiated Demand Driven protocols. They are called so because the routes are discovered only when needed by source.Source initiated on demand networks cerates routing only when desired by the source node. When source wants to communicate with destination then it invokes the route discovery mechanism to find the path to the destination. The route discovery process is completed once a route is found or all possible are identified. Once the rout is formed between source and destination it is maintained by a route maintenance procedure until the destination becomes inaccessible or the route is no longer desired. (Chang)These Examples of reactive routing protocols are dynamic Source Routing (DSR), Ad hoc on-demand distance vector routing AODV, ABR, SSA, CBRP, and RDMAR.2.10.2.1 AODV (Ad hoc On Demand Distance Vector)Ad hoc On Demand Distance Vector protocol as the name implies it is an On Demand that is, Reactive Protocol. AODV is capable of both unicast and multicast routing. It is an on demand algorithm, it means that it builds routes between nodes only as desired by source nodes. It uses the concepts of DSR routing for route discovery and route maintenance and DSDV protocol for the concept of sequence number. It uses sequence number concept to ensure the freshness of routes. The ad hoc on-demand Distance vector algorithm facilitates the self-starting, multi hop and dynamic routing between partici pating nodes to establish and maintain an ad hoc network. AODV algorithm enables the nodes to find the routes for new destinations as and when they are needed and the nodes are not required to maintain the routes to the destination that are not in the part of active communication. It also enables the nodes in the formation of multicast groups and enables the nodes to respond quickly to link breakages and topological changes in the network thus the operation of AODV is loop free and thus avoids the Balham Ford count to infinity problem.AODV routing protocol is a simple and effective routing protocol for Ad hoc networks. It also uses the concept of hop by hope routing and sequence numbers from DSDV protocol.The following are the message types defined by AODV they areRoute request (RREQ),Route replies (RREP),Route error (RERR) and group hellos (GRPH) this message types are handled by UDP and IP header.The route request message format contains the following fieldsSource address the addr ess of the node which originates the route requestSource Sequence number the current sequence number to be used in deciding the route for the source requestDestination address the address of the target node for which the route is initialized.Destination Sequence numbers the sequence number received by source for route towards the destination.Broadcast ID The sequence number by which a RREQ route request can be uniquely identified.Hop counts the number of the hops to be taken from the source node to reach the destination node that handles the Route request.The Route Reply message format contains the following fieldsDestination address the address of the destination node for which the route is aboundedDestination sequence number the destination sequence number related to the routeSource address the address of the source node that originates the route requestLifetime the time for which nodes receiving the route reply considers the route to be valid.Hop counts the number of hops to be t aken from source to destination.The route error message format contains the following fieldsUnreachable destination address The address of the destination that has become unreachable due to link failure. (Arbia, 2008)In AODV the only nodes that take active participation in routing process are the nodes that sit in direct path between source and destination. The nodes which do not lie on active path do not take participate or maintain the routing table, thus AODV minimize the number of control messages sent between two nodes. As long as there is a valid routes between the source and destination for communication, AODV does not play any role and when a new route to a new destination is required and if the route to the destination does not exist only then the source node initialize the route discovery process by broadcasting the RREQ message to find the route to destination. The
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