Zigbee is a non-infrastructural wireless network which has low data rate and self-reconstruct capacity. There are two routing algorithms for Zigbee mesh network : Tree routing and On Demand routing. If the parameter is setting improperly in a large scale of network, Tree routing algorithm will cause the problem of device addressing. Some researches show that the efficiency of On Demand routing is as well as the Tree routing in periodic data transmition. Therefore, this paper attempts to using On Demand routing protocol to construct the data transfer path in symmetric street light structure. Like AODV(Ad-hoc On-demand Distance vector), we must reduce control message to find the route in limited bandwidth network. We propose AODV-BN(Backup Next) according to Sung-Ju Lee and Mario Gerla¡¦s algorithm, ¡§AODV-BR¡¨. AODV-BN only use RREP message to find the back up node and get the neighbor table by eavesdropping instead of sending Hello Message. So we can use very small amount of control messages to fix the broken route and reduce the collision. Finally, we use NS-2(Network Simulation) to simulate the performance of AODV-BN. The simulation results present that our methods reduce the control message indeed and improve the throughput of the network.

This diploma thesis focuses on the MANET Network (Mobile Ad-Hoc Network). There are theoretically elaborated basic information, the characteristics of the MANET network and great emphasis is placed on routing in these networks. In the next chapter the diploma thesis focuses on the Ad Hoc Demand Distance Vector (AODV) routing protocol. It features the characteristics of this protocol and the principle of communication and routing in MANET networks. Hereinafter, the individual reports of the AODV protocol are described in detail. In the third chapter, the thesis introduces the NS-3 simulation environment (network Simulator - 3) and then deals with the design of the MANET network in NS-3 using the AODV routing protocol. The practical part of the diploma thesis is the MANET network simulation and testing with the AODV routing protocol. Laboratory task is built from these simulations and the results of the testing.

As the growth of multimedia communications involving digital audio and video, it is increasingly important for the MANET (Mobile Ad Hoc Network) routing protocols to simultaneously support both real-time and non-real-time traffic. MANET energy management should offer this support because devices are equipped with limited battery power. To achieve this end, we revise the Ad hoc On-demand Distance Vector (AODV) routing protocol to provide an energy management mechanism such that both real-time and non-real-time packets can be effectively transmitted. In the proposed scheme, real-time traffic uses higher transmission power to reduce transmission delay time and selects a shortest route with the largest minimum residual energy to avoid route break. The non-real-time traffic uses normal transmission power to save energy and chooses a proper shortest route with highest average residual energy to balance node energy consumption. The simulation results show that the revised AODV obtains lower average end-to-end delay and fewer energy-exhausted nodes comparing to the conventional AODV.

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Les travaux de recherche menés dans le cadre de cette thèse concernent l'amélioration du débit et de la qualité de service dans les réseaux sans fil basés sur les standards de la famille 802.11. Des simulations exhaustives ont été menées pour l'analyse et l'évaluation des performances des protocoles de routages réactifs AODV, DSR et DYMO ainsi que des protocoles de routage proactifs DSDV, FSR et OLSR. Plusieurs paramètres ont été considérés comme la mobilité des noeuds la charge du réseau et la mise à l'échelle. Nous pouvons observer que la métrique de qualité de lien est un paramètre important dans toute stratégie de routage. L'objectif du présent travail est de proposer une analyse comparative des différents protocoles de routage, basée sur les métriques de qualité de lien et de proposer une nouvelle métrique permettant d'améliorer le routage en termes de routage et de délai bout-en-bout. Dans la disparité des métriques proposées dans la littéraire, la métrique ETX (Expected Transmission Count) a été largement utilisée. Aussi, nous focaliserons, principalement, sur les métriques basées sur ETX. Notre constatation est que les besoins en termes de qualité de service dans les réseaux sans fil multi-saut, sont affecté entre autre par le protocole de routage adopté et la métrique de lien utilisée. Cependant, ceci est aussi strictement lié à la qualité des canaux de communication au niveau physique et l'état des files d'attente au niveau MAC. Aussi, une nouvelle métrique de qualité de lien est proposée, basée sur ETX et appelée IBETX (Interference and Bandwidth Adjusted ETX). Cette nouvelle métrique prend en considération les effets de l'interférence et de l'impact de l'état de la couche MAC sur les performances des liens de communication. Des simulations ont été conduites sous NS-2 afin de montrer l'intérêt de la métrique utilisée. Ainsi IBETX améliore le débit efficace de 19% par rapport à ETX et de 10% par rapport à ETP (Expected Throughput). Par ailleurs, la métrique proposée réduit le délai bout en bout de 16% par rapport à ELP ( Expected Link Performance) et de 24% par à ETX / This dissertation endeavors to contribute enhancements in goodputsof the IEEE 802.11-based Wireless Multi-hop Networks (WMhNs).By performing exhaustive simulations, for the deep analysis and detailed assessment of both reactive (AODV, DSR, DYMO) and proactive (DSDV, FSR, OLSR) protocols for varying mobilities, speeds, network loads and scalabilities, it is observed that a routing link metric is a significant component of a routing protocol. In addition to finding all available paths, the fastest end-to-end route is selected by a link metric for the routing protocol. This study aims the quality routing. In the class of quality link metrics, Expected Transmission Count (ETX) is extensively used. Thus, the most recently proposed ETX-based metrics have been analyzed. Though, newly developed metrics over perform ETX but still they can be improved. By profound analysis and particularized comparison of routing protocols depending upon their classes (reactive and proactive) and ETX-based metrics, we come to realize that users always demand proficient networks. In fact, WMhNs are facing several troubles which they expect to be resolved by the routing protocol operating them. Consequently, the protocol depends upon the link metric for providing quality paths. So, we identify and analyze the requirements to design a new routing link metric for WMhNs. Because, considering these requirements, when a link metric is proposed, then : firstly, both the design and implementation of the link metric with a routing protocol become easy. Secondly, the underlying network issues can easily be tackled. Thirdly, an appreciable performance of the network is guaranteed. Keeping in view the issues of WMhNs, increasing demands of users and capabilities of routing protocols, we propose and implement a new quality link metric, Interference and Bandwidth Adjusted ETX (IBETX). As, MAC layer affects the link performance and consequently the route quality, the metric therefore, tackles the issue by achieving twofold MAC-awareness. Firstly, interference is calculated using cross-layered approach by sending probes to MAC layer. Secondly, the nominal bit rate information is provided to all nodes in the same contention domain by considering the bandwidth sharing mechanism of 802.11. Like ETX, our metric also calculates link delivery ratios that directly affect throughput and selects those routes that bypass dense regions in the network. Simulation results by NS-2 show that IBETX gives 19% higher through put than ETX and 10% higher than Expected Throughput (ETP). Our metric also succeeds to reduce average end-to-end delay up to 16% less than Expected Link Performance (ELP) and 24% less than ETX

The key challenge in mobile ad-hoc network (MANET) is the design of routing protocol which adapting their behavior to frequency with rapid changes in the network. As we have known, there are two main kinds of routing protocols in MANET: proactive and reactive routing protocol; and in addition, authors [1] proposed to use location information provided by positioning devices such as global positioning systems (GPS) to assist routing. We wonder whether the assumption of all devices in the communication area have the GPS ability is reasonable; furthermore, a GPS-enabled device has its own limitation on working areas; for example, the GPS ability cannot work in the indoor environments. In this paper, (1) we tried to addition the mechanism of probing routing redirection/discovery at routing protocol in AODV. Using overheard node avoid route breaking and select route batter than origin.(2)we tried to use the property of GPS to solve the routing problems in MANET, which like broadcast storm in the route discovery, device power saving and optimal one-hop destination, channel reuse rate, and optimal routing path. According to 802.11 specification, the best way to reach the goal of device power saving is putting device into the sleep mode. In this routing protocol, we let most mobile devices stay in the sleep mode until it sends or receives data or acts as an intermediate node to forward data. Last, we use simulations and implementation to validate the effectiveness of our design.

The main task of this master’s thesis is to simulate the routing protocol AODV (Adhoc On-Demand Distance Vector Routing) to the Network Simulator ns-3 environment, and to realize a model of MANET (Mobile Ad-hoc Network) network with the support of Quality Of Service (QoS). Further implement the protocol AODV in real devices and the involvement of such nodes in the simulation process using the simulator ns-3. This work provides the theoretical basics: it deals with the primary characteristics of MANET, describes in detail the routing protocols MANET with support of QoS, provides information about the Network Simulator ns-3 simulation environment, describes in detail the existing implementation solutions of the protocol AODV in to real devices and provides information about the methods of involvement real devices to the simulation.

This thesis contains a theoretical basis for MANET networks. The main focus of the thesis is principles of these networks, their routing protocols and especially on Ad hoc On-Demand Distance Vector (AODV), implementation of this protocol and implementation of new mechanis for peer selection. Thesis contains ETX metric basic and implementation of this metric to AODV protocol. There is a demonstration of simulation of AODV protocol and simulation of AODV-ETX protocol. Simulations are run in Network Simulator 3. AODV and AODV-ETX comparasion are included in thesis.

Broadcasting is an essential and effective data propagation mechanism with several important applications, such as route discovery, address resolution and many other network services. Though data broadcasting has many advantages, it can also cause a high degree of contention, collision and congestion, leading to what is known as 'broadcast storm problems'. Broadcasting has traditionally been based on the flooding protocol, which simply overflows the network with a high number of rebroadcast messages until these reach all the network nodes. A good probabilistic broadcast protocol can achieve high saved rebroadcast (SRB), low collision and a lower number of relays. When a node is in a sparse region of the network, rebroadcasting is relatively more important while the potential redundancy of rebroadcast is low because there are few neighbours which might rebroadcast the packet unnecessarily. Further, in such a situation, contention over the wireless medium resulting from Redundant broadcasts is not as serious as in scenarios with medium or high density node populations. This research proposes a dynamic probabilistic approach that dynamically fine-tunes the rebroadcast probability according to the number of neighbouring nodes distributed in the ad-hoc network for routing request packets (RREQs) without requiring the assistance of distance measurements or location-determination devices. The main goal of this approach is to reduce the number of rebroadcast packets and collisions in the network. The performance of the proposed approach is investigated and compared with simple AODV, fixed-probabilistic and adjusted-probabilistic flooding [1] schemes using the GloMoSim network simulator and a number of important MANET parameters, including node speed, traffic load and node density under a Random Waypoint (RWP) mobility model. Performance results reveal that the proposed approach is able to achieve higher SRB and less collision as well as a lower number of relays than fixed probabilistic, simple AODV and adjusted-probabilistic flooding. In this research, extensive simulation experiments have been conducted in order to study and analyse the proposed dynamic probabilistic approach under different mobility models. The mobility model is designed to describe the movement pattern of mobile customers, and how their position, velocity and acceleration change over time. In this study, a new enhanced dynamic probabilistic flooding scheme is presented. The rebroadcast probability p will be calculated dynamically and the rebroadcasting decision will be based on the average number of nodes in the ad-hoc networks. The performance of the new enhanced algorithm is evaluated and compared to the simple AODV, fixed-probabilistic, adjusted-probabilistic and dynamic-probabilistic flooding schemes. It is demonstrated that the new algorithm has superior performance characteristics in terms of collision, relays and SRB. Finally, the proposed schemes are tested and evaluated through a set of experiments under different mobility models to demonstrate the relative merits and capabilities of these schemes.

The research study determines OPNET simulation to evaluate the MANET routing protocols i.e. AODV, DSR, GRP and OLSR performance for HTTP and FTP base application traffic. Results from the simulation result helps to measure the performance matrix i.e. packet delivery fraction, normalized routing load, throughput and end to end delay. Scalar values are extracted from simulation to plot desired performance graphs to analyze. The research results and conclusion produces enough information for the selection of best routing protocol for MANET in terms of HTTP and FTP application types.