Dissertations / Theses: 'MANETs'

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Krichène, Mohamed Foued. "Contacts in MANETs." [S.l.] : Universität Stuttgart / Fakultät Informatik, Elektrotechnik und Informationstechnik, 2003. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11144239.

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Ur-Rehman, Shoaib, and Irshan Ullah. "Analysis of Black Hole attack on MANETs Using different MANET routing protocol." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1151.

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ABSTRACT Wireless networks are gaining popularity day by day, as users want wireless connectivity irrespective of their geographic position. There is an increasing threat of malicious nodes attacks on the Mobile Ad-hoc Networks (MANET). Black hole attack is one of the security threat in which the traffic is redirected to such a node that actually does not exist in the network. It’s an analogy to the black hole in the universe in which things disappear. MANETs must have a secure way for transmission and communication which is quite challenging and vital issue. In order to provide secure communication and transmission, researcher worked specifically on the security issues in MANETs, and many secure routing protocols and security measures within the networks were proposed. The scope of this thesis is to study the effects of Black hole attack in MANET using both Proactive routing protocol i.e. Optimized Link State Routing (OLSR) and Reactive routing protocol Ad-Hoc on Demand Distance Vector (AODV). Comparative analysis of Black Hole attack for both protocols is taken into account. The impact of Black Hole attack on the performance of MANET is evaluated finding out which protocol is more vulnerable to the attack and how much is the impact of the attack on both protocols. The measurements were taken in the light of throughput, end-to-end delay and network load. Simulation is done in Optimized Network Engineering Tool (OPNET). Previously the works done on security issues in MANET were based on reactive routing protocol like Ad-Hoc on Demand Distance Vector (AODV). Different kinds of attacks were studied, and their effects were elaborated by stating how these attacks disrupt the performance of MANET.

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ULLAH, IRSHAD, and SHOAIB UR REHMAN. "Analysis of Black Hole Attack on MANETs Using Different MANET Routing Protocols." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2505.

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Wireless networks are gaining popularity to its peak today, as the users want wireless connectivity irrespective of their geographic position. There is an increasing threat of attacks on the Mobile Ad-hoc Networks (MANET). Black hole attack is one of the security threat in which the traffic is redirected to such a node that actually does not exist in the network. It’s an analogy to the black hole in the universe in which things disappear. The node presents itself in such a way to the node that it can attack other nodes and networks knowing that it has the shortest path. MANETs must have a secure way for transmission and communication which is quite challenging and vital issue. In order to provide secure communication and transmission, researcher worked specifically on the security issues in MANETs, and many secure routing protocols and security measures within the networks were proposed. Previously the works done on security issues in MANET were based on reactive routing protocol like Ad-Hoc On Demand Distance Vector (AODV). Different kinds of attacks were studied, and their effects were elaborated by stating how these attacks disrupt the performance of MANET. The scope of this thesis is to study the effects of Black hole attack in MANET using both Proactive routing protocol i.e. Optimized Link State Routing (OLSR) and Reactive routing protocol Ad-Hoc On Demand Distance Vector (AODV). Comparative analysis of Black Hole attack for both protocols is taken into account. The impact of Black Hole attack on the performance of MANET is evaluated finding out which protocol is more vulnerable to the attack and how much is the impact of the attack on both protocols. The measurements were taken in the light of throughput, end-to-end delay and network load. Simulation is done in Optimized Network Engineering Tool (OPNET).

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Gironés, Quesada Luis. "A Routing Protocol for MANETs." Thesis, Norwegian University of Science and Technology, Department of Telematics, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9513.

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In this master thesis there has been a description of what MANETs are and why they are so interesting. Because of its characteristics, the tradicional routing protocols for wired networks are not advisable for them. A specific routing protocol for MANETs is necessary. In this thesis the main groups of these protocols have been explained and some of the most commonly used of them were studied. We saw that each protocol is better in a specific environment. None of them are perfect for all the ranges of nodes mobility, traffic, number of nodes, etc. The two main groups of protocols studied are the proactive and the reactive ones. The main characteristic of the proactive is that each node maintains a route to every node in the network. Besides, it periodically updates this information. No matter if there is communication between the nodes or not. As representative examples of proactive protocols, OLSR and DSDV were described here. On the other hand, in the reactive ones the nodes only calculate the routes between those nodes that want to communicate. This kind of protocols perform in a more efficient usage of the bandwith (which is very limited in the MANETs medium) and the resources of the nodes. However, as a drawback, when the route is not available yet, the delay to achieve it can be great. The reactive protocols choosen here to be studied were AODV and DSR. In the reactive, the main problem is the delay to achieve a new route. In the proactive, it is the high usage of resources and bandwith when it is not necessary. Both, reactive and proactive also have the problem of the scalability. To solve these problems, a new kind of protocols appeared: the hybrid ones. A hybrid routing protocol combines both, the proactive and reactive to achieve better performance. The most popular of them is ZRP and its operation was described here too. None of the existing protocols are suitable for a MANET with a large number of nodes, each one of them with a different velocity and traffic. ZRP solves in part the problem of the scalabilty, but under different patterns of traffic and nodes velocity performs worse than the OLSR, DSR and AODV. Understanding the strengths and weaknesses of each protocol, a new one was proposed. The objective of this new protocol was to be suitable to MANETs with nodes moving freely, with different ranges of speed and traffic. Also, another objective was to improve the scalability of the reactive and proactive protocols. The protocol proposed here was called Penaguila. As ZRP and other hybrid routing protocols, it is based on having some nodes working in proactive mode creating areas, and comunicating this areas with other nodes working in reactive mode. The difference between Penaguila and ZRP, is that Penaguila takes into acount the speed and traffic of each node. Therefore, Penaguila tries to have each node working in the mode more suitable for itself. Also, an evaluation of the OLSR, AODV, DSR, ZRP and Penaguila has been done. Since it was not possible to program Penaguila in NS-2 because of the short time to write the thesis, it was only feasible to do a qualitative study. In this study the advantages and disadvantages of each protocol were exposed and the concluision was that Penaguila can outperform the existing protocols when: A) The network is large, since it is a hierarchical routing protocol. B) The nodes have very different speeds and amount of traffic.

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Pham, Vinh. "Performing Gateway Load Balancing in MANETs." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for telematikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-15131.

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During the last decades, the advances in Information Technology have formed the basis for increased interest and research activity in the field of ad hoc wireless multihop networks or simply ad hoc networks. This emerging technology enables internetworking between wireless nodes that are deployed in an ad hoc and temporary manner. All nodes in an ad hoc network take the role as both hosts in an end-to-end communication session, or as routers to collaboratively relay data traffic in a multihop fashion on behalf of other nodes. Furthermore, ad hoc networks are highly dynamic in nature, i.e. nodes can join or leave the network at any time, and additionally, the nodes have also the flexibility to move around while being in the network. The fact that ad hoc networks can be rapidly deployed with minimal prior planning, cost, and without the need of any pre-existing infrastructure makes this technology very attractive and suitable in a number of applications, including emergency and rescue operations, and military operations. Although ad hoc networks represent a promising technology that offers a broad range of potential useful applications, this technology is still in an immature phase. There are yet many issues and challenges that need to be resolved, which mainly arise from the inherent unreliability of wireless communication, the dynamic nature of these networks, the limited availability in resources with respect to bandwidth, processing capacity, battery power, and from the possibly large scale of these networks. These challenges require that the networking protocols at all layers in the network stack, that in many cases were originally designed for wired networks, must be modified or optimized, in order to adapt to the characteristic of the wireless environment. The focus of this thesis has been devoted to the investigation of two specific issues within the field of ad hoc networking, i.e. node mobility and load balancing. The aim is to provide solutions in order to improve the overall performance in ad hoc networks. Node mobility is one of the most important features in ad hoc networks, however, it is also the reason for frequent link breaks and the constant change in the topology. An ongoing data transmission that is interrupted by a link break, must be rerouted to alternative paths in order to circumvent the broken link. However, this process of rerouting traffic takes a certain amount of time, which is referred to as the rerouting time. Minimizing the rerouting time is essential in order to reduce packet loss and improve network performance. In this thesis we investigate the factors that affect the rerouting time in proactive routing protocols and propose solutions for minimizing it. Load balancing refers to the process of distributing traffic load more evenly in the network in order to minimize congestion and to optimize the usage of network resources. Performing load balancing in ad hoc networks is generally very challenging due to the inherently interfering nature of the wireless medium. In this thesis we therefore investigate the feasibility and the potential benefits of performing load balancing in ad hoc networks. We consider two scenarios, i.e. load balancing for intradomain and interdomain traffic. Intradomain traffic is traffic between nodes inside an ad hoc network. Performing load balancing on intradomain traffic can be done in two ways. The first is referred to as multipath load balancing where a traffic flow between a source and destination pair is distributed over multiple alternative disjoint/semi-disjoint paths. The aim is to maximize throughput and reduce the risk for packet loss. However, a number of previous work has investigated and reported that this type of load balancing can only provide a rather limited improvement in performance due to the interference between the paths [1] [2]. Due to this reason, multipath load balancing is therefore not considered in this thesis. Instead we focus on the second way which is referred to as transit routing. Transit routing is about routing part of the local traffic over a backbone network in order to relief the traffic load in the ad hoc network. The assumption behind this concept is a network architecture similar to a Wireless Mesh Network (WMN), where a high capacity backbone network is an integrated part of the Mobile Ad hoc Network (MANET). This backbone network is commonly used to provide Internet-connectivity services, but can also be exploited to alleviate the traffic load in the MANET. In addition, for certain source and destination pairs, performing transit routing can considerably increase the throughput compared to if the traffic is routed within the ad hoc network. Interdomain traffic refers to traffic between a node inside the ad hoc network and a remote node outside of the ad hoc network. Load balancing for interdomain traffic considers the potential of distributing interdomain traffic among multiple gateways in order to avoid congestion at the gateways and maximize the capacity for interdomain traffic. This type of load balancing is commonly referred to as gateway load balancing in the literature. Furthermore, interdomain can either be inbound or outbound traffic. The work in this thesis mainly focuses on performing load balancing for outbound traffic. However, we believe that the results in our work are also applicable to inbound traffic as well. The main contributions in this thesis are the investigation and the proposals of different solutions for intradomain and interdomain load balancing.

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Xu, Sanlin, and SanlinXu@yahoo com. "Mobility Metrics for Routing in MANETs." The Australian National University. Faculty of Engineering and Information Technology, 2007. http://thesis.anu.edu.au./public/adt-ANU20070621.212401.

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A Mobile Ad hoc Network (MANET) is a collection of wireless mobile nodes forming a temporary network without the need for base stations or any other preexisting network infrastructure. In a peer-to-peer fashion, mobile nodes can communicate with each other by using wireless multihop communication. Due to its low cost, high flexibility, fast network establishment and self-reconfiguration, ad hoc networking has received much interest during the last ten years. However, without a fixed infrastructure, frequent path changes cause significant numbers of routing packets to discover new paths, leading to increased network congestion and transmission latency over fixed networks. Many on-demand routing protocols have been developed by using various routing mobility metrics to choose the most reliable routes, while dealing with the primary obstacle caused by node mobility. ¶ In the first part, we have developed an analysis framework for mobility metrics in random mobility model. Unlike previous research, where the mobility metrics were mostly studied by simulations, we derive the analytical expressions of mobility metrics, including link persistence, link duration, link availability, link residual time, link change rate and their path equivalents. We also show relationships between the different metrics, where they exist. Such exact expressions constitute precise mathematical relationships between network connectivity and node mobility. ¶ We further validate our analysis framework in Random Walk Mobility model (RWMM). Regarding constant or random variable node velocity, we construct the transition matrix of Markov Chain Model through the analysis of the PDF of node separation after one epoch. In addition, we present intuitive and simple expressions for the link residual time and link duration, for the RWMM, which relate them directly to the ratio between transmission range and node speed. We also illustrate the relationship between link change rate and link duration. Finally, simulation results for all mentioned mobility metrics are reported which match well the proposed analytical framework. ¶ In the second part, we investigate the mobility metric applications on caching strategies and hierarchy routing algorithm. When on-demand routing employed, stale route cache information and frequent new-route discovery in processes in MANETs generate considerable routing delay and overhead. This thesis proposes a practical route caching strategy to minimize routing delay and/or overhead by setting route cache timeout to a mobility metric, the expected path residual time. The strategy is independent of network traffic load and adapts to various non-identical link duration distributions, so it is feasible to implement in a real-time route caching scheme. Calculated results show that the routing delay achieved by the route caching scheme is only marginally more than the theoretically determined minimum. Simulation in NS-2 demonstrates that the end-to-end delay from DSR routing can be remarkably reduced by our caching scheme. By using overhead analysis model, we demonstrate that the minimum routing overhead can be achieved by increasing timeout to around twice the expected path residual time, without significant increase in routing delay. ¶ Apart from route cache, this thesis also addresses link cache strategy which has the potential to utilize route information more efficiently than a route cache scheme. Unlike some previous link cache schemes delete links at some fixed time after they enter the cache, we proposes using either the expected path duration or the link residual time as the link cache timeout. Simulation results in NS-2 show that both of the proposed link caching schemes can improve network performance in the DSR by reducing dropped data packets, latency and routing overhead, with the link residual time scheme out-performing the path duration scheme. ¶ To deal with large-scale MANETs, this thesis presents an adaptive k-hop clustering algorithm (AdpKHop), which selects clusterhead (CH) by our CH selection metrics. The proposed CH selection criteria enable that the chosen CHs are closer to the cluster centroid and more stable than other cluster members with respect to node mobility. By using merging threshold which is based on the CH selection metric, 1-hop clusters can merge to k-hop clusters, where the size of each k-hop cluster adapts to the node mobility of the chosen CH. Moreover, we propose a routing overhead analysis model for k-hop clustering algorithm, which is determined by a range of network parameters, such as link change rate (related to node mobility), node degree and cluster density. Through the overhead analysis, we show that an optimal k-hop cluster density does exist, which is independent of node mobility. Therefore, the corresponding optimal cluster merging threshold can be employed to efficiently organise k-hop clusters to achieve minimum routing overhead, which is highly desirable in large-scale networks. ¶ The work presented in this thesis provides a sound basis for future research on mobility analysis for mobile ad hoc networks, in aspects such as mobility metrics, caching strategies and k-hop clustering routing protocols.

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Lüthy, Michael. "Bild und Blick in Manets Malerei /." Berlin : Gebr. Mann, 2003. http://catalogue.bnf.fr/ark:/12148/cb38990881x.

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Xu, Sanlin. "Mobility metrics for routing in MANETs /." View thesis entry in Australian Digital Theses Program, 2007. http://thesis.anu.edu.au/public/adt-ANU20070621.212401/index.html.

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Shariat, Shahin. "Spectrum-aware routing in cognitive radio MANETs." Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/845510/.

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Cognitive Radio (CR) provides a promising means to the more efficient use of available spectrum. Routing in multi-hop wireless networks remains challenging and introduction of CR technology has created additional demands on routing within Cognitive Radio Mobile Ad-hoc Networks (CR-MANETs). To address these challenges, spectrum-aware routing protocols aiming at dynamic utilization of the so-called spectrum opportunities have been developed recently to improve end-to-end performance of the network for example in terms of Delay, Packet Loss and Throughput. One of the bottlenecks in the performance of ad hoc networks has been the lack of a load balancing mechanism. With the addition of potential routing opportunities introduced by CR technology, a load balanced routing protocol which can utilize SOPs into the load balancing mechanism is a missing puzzle in the problem of routing in CR-technology. Quantum game theory provides a framework to utilize entangled particles with the aim of affecting decision-making process of distant players. Hence, this theory has the potential to be used as a framework to target the load balancing problem in ad hoc networks. First, a novel spectrum-aware routing protocol based on OLSR as the basis of implementation is proposed in this research. The proposed algorithm utilizes ETX as the link quality estimation metric and provides the best weigh end-to-end paths based on generalization of Dijkstra’s algorithm to multigraphs. The results demonstrate that the proposed algorithm outperforms the existing baseline OLSR routing algorithm. Due to the instability in the end-to-end delay performance of the proposed algorithm, backpressure algorithm is identified as a potential solution to stabilize queues in the network and target the shortcoming of the proposed algorithm. Hence, a novel spectrum-aware routing algorithm based on backpressure load balancing mechanism is proposed and compared against the baseline OLSR and the proposed spectrum-aware OLSR algorithm. The OLSR backpressure spectrum-aware (OLSR-BSA) routing algorithm not only optimizes route computation based on the predefined cost metric but also incorporates the queue gradients of backpressure algorithm to perform load balancing. The results proof that the backpressure algorithm can efficiently utilize the SOPs in the load balancing optimization problem and results a performance and stability gain both in terms of end-to-end delay and packet delivery ratio. The instability resulted by inaccuracy of queue information in the proposed OLSR-BSA algorithm motivated our research to explore the problem of load balancing from a completely new perspective of quantum game theory. We have formulated the problem of load balancing in ad hoc networks using quantum game theory and proposed a novel routing algorithm so called Quantum Load Balanced OLSR (QLB-OLSR). The simulation results demonstrate a significant load balancing stability gain against the baseline OLSR routing algorithm.

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Jazyah, Yahia Hasan. "Modified location aided routing protocol for UWB MANETs." Thesis, University of Salford, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543508.

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Qadri, Nadia Nawaz. "Robust P2P Video Streaming over MANETs and VANETs." Thesis, University of Essex, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520109.

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Hurley-Smith, Darren. "Virtual closed networks : optimised security for autonomous MANETs." Thesis, University of Greenwich, 2015. http://gala.gre.ac.uk/20953/.

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Autonomous mobile platforms (such as Unmanned Aerial Vehicles, also known as UAVs) have become a popular tool in exploration, disaster management, civil-engineering, agricultural and military scenarios. Their endurance, low-cost, high mobility and ability to reduce human involvement in prolonged or hazardous activities have proven attractive to both commercial and military sectors. In such domains, security is required to protect the data, functionality and performance of the network, making it a vital consideration when developing such systems. Systems capable of independent action, following a human-defined mission without scripting or other forms of direction in the field, are adaptable and effective as a means of achieving individually simple tasks that due to their number and distribution represent complex objectives as a collective. However, such systems must communicate to achieve autonomous function. Efficient distribution of tasks requires significant communication between all members of the network to determine the nodes most fit to undertake a given task. Mobile ad hoc networks (MANETs) provide the foundation for such communication, providing a means by which nodes may communicate with other members of the network, even if they are not in range. Issues arise when considering the security of MANET communication, due to the ease observation, interception and manipulation of data broadcast over such networks. It is trivial for attackers to perform such actions, due to the open nature of the communication medium. This dissertation presents a novel security framework, which specifically targets autonomous MANET communication. Addressing the open-medium problem by providing a Virtual Closed Network (VCN) environment, Security Using Pre-Existing Routing for MANETs (SUPERMAN) also secures routing and control data, providing confidentiality, integrity and authentication services as a complete solution the network layer and above. Improvements to the efficiency of communication required by distributed task allocation are proposed (Cluster Form CBBA and Broadcast Enabled Cluster Form CBBA) based on this work, in the interests of optimising the use of network resources to facilitate the addition of robust security measures suitable for resource constrained MANETs.

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Shiferaw, Addisalem Negash. "Mobility and Interest Aware Information Sharing in MANETs." Lyon, INSA, 2010. http://theses.insa-lyon.fr/publication/2010ISAL0052/these.pdf.

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In this thesis, we propose an advertisement-based middleware called SAMi to allow nomadic users to share information according to their interests, contexts and stay times. In SAMi, information sharing is usually by distributing advertisements and queries. In order not to overload the environment with unnecessary advertisements and queries, we propose an approach to parameterise advertisement policies according to users’ profiles and contexts. The parameterisation process is performed semi-automatically by analysing users’ information sharing activities. SAMi classifies files hierarchically and presents them in a file tree. Files are advertised according to user’ profile and context. During advertisements, the middleware advertises files by using descriptions at the shallow and depth level of the file tree. Users have a lot of information to share with each other. If files to be shared are not controlled, the overloading of information will hinder the sharing activity. Consequently, we propose to select sharable files according the users’ interests. Users can specify their interests to receive/provide information reactively. Users’ interests can also be automatically determined by using association rules and by analysing their social networks. SAMi has been deployed in a simulated environment and over real devices interconnected by Bluetooth. From the evaluations that have been made, we have observed that SAMi has a very good potential to serve nomadic users to share information according
Dans cette thèse, nous proposons un middleware appelé SAMi pour permettre aux utilisateurs nomades de partager l'information en fonction de leurs intérêts, les contextes et leurs temps de connexion. Dans SAMi, le partage de l’information est effectué par la distribution d’annonces et de requêtes. Afin d’éviter la surcharge de l’environnement avec des annonces et des requêtes inutiles, nous proposons une approche pour paramétrer les politiques d’annonces en fonction des profils des utilisateurs et de leurs contextes. Le processus de paramétrages est effectué semi-automatiquement par l’analyse des activités de partage d’informations. SAMi classe hiérarchiquement des fichiers et les présente dans une structure appelée une arborescence de fichiers. Au cours du processus d’annonces, le middleware procède à un annoncement des fichiers en utilisant soit (i) une description détaillée (situé à un niveau profond dans l’arborescence des fichiers , soit (ii) une description générale (située à un niveau peu profond). Vu la quantité massive d’informations à partager, un contrôle/filtrage de fichiers est mis en place pour éviter la surchage du réseau qui peut empêcher d’aboutir l’activité de partage. Par conséquent, nous proposons que les fichiers partageables soient choisis en fonction des intérêts des utilisateurs. Les utilisateurs peuvent spécifier leurs intérêts à concevoir ou à fournir des informations de manière réactive. Les intérêts des utilisateurs peuvent également être automatiquement déterminés en utilisant les règles d’associations et réseaux sociaux. SAMi a été testé dans deux environnements ; un simulé et un autre réel en le déployant sur des dispositifs mobiles reliés entre eux par Bluetooth. Les évaluations qui ont été faites, nous ont permis de conclure que SAMi a un bon potentiel pour aider les utilisateurs nomades à partager l’information en fonction de leurs intérêts

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Costa, Rui Pedro Ferreira da. "Test and measurement environments for VANETs and MANETs." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/1975.

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Mestrado em Engenharia de Computadores e Telemática
A crescente necessidade por parte dos utilizadores em obterem acesso à Internet “em qualquer lugar e qualquer momento” tem incentivado investiga ção e desenvolvimento de abordagens capazes de resolver esta questão. Um dos maiores obstáculos em fornecer uma solução de acesso ubíquo à Internet tem sido a gestão de mobilidade. Nesta Tese de Mestrado ir-se-á implementar uma das soluções correntemente em desenvolvimento, integrando-a num ambiente MANET. A plataforma resultante pode ser posteriormente avaliada e até retiradas medidas de desempenho, podendo-se ainda tirar conclusões importantes sobre como um ambiente MANET se comporta numa plataforma de mobilidade global e acesso ubíquo. Na àrea de Sistemas de Transporte Inteligentes, tópicos como eficiência de tráfego e segurança dos utilizadores têm-se mostrado muito populares e deram in´ıcio a pesquisa extensiva em Redes Veículares Ad-Hoc (VANETs). Métodos tradicionais para investigação e desenvolvimento como testes com protótipos ou simulação computacional têm sido largamente usados. No entanto, os testes com protótipos são usualmente muito caros e a simulação computacional tem falta de precisão em ambientes sem fios. Esta Tese de Mestrado tem também por objectivo construir uma solução híbrida que combine os métodos de emulação e simulação. A solução proposta será implementada num testbed para VANETs. O testbed resultante irá permitir que multiplas instâncias de programas de routing reais possam ser executadas sobre um ambiente simulado computacionalmente. Assim poderão ser também retiradas elacções sobre o seu desempenho em características como o consumo de recursos e escalabilidade. ABSTRACT: The growing need from users to have internet access “whenever and wherever” has driven research to devise several approaches to cope with this issue. One of the greatest challenges in providing ubiquitous internet access has been the management of mobility. In this Master Thesis a solution currently under development, will be implemented integrating a MANET environment. The resulting testbed can later be evaluated and it’s performance measured, drawing important conclusions about how a MANET environment behaves in a global mobility and ubiquitous access framework. In the area of Intelligent Transportation System traffic efficiency and safety for users have become very popular topics and have triggered extensive research in Vehicular Ad-Hoc Networks (VANETs). Traditional methods for reaserch and development like field testing and simulation have been used. But field testing is usually very expensive expensive and simulation lacks accuracy in wireless environments. This Master Thesis also aims to provide a hybrid solution that combines the simulation and emulation methods. The proposed solution is implemented in a testbed for VANETs. The resulting testbed would allow multiple real routing instances to run simultaneously on a simulated environment. And to provide performance measures such as resource consumption and scalability.

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Kabir, Mashud. "Region-based adaptation of diffusion protocols in MANETs." [S.l. : s.n.], 2003. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11144235.

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Parthasarathy, Madhusoodan. "Routing in the presence of groups in MANETs." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Spring2009/m_parthasarathy_020409.pdf.

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Thesis (M.S. in computer science)--Washington State University, May 2009.
Title from PDF title page (viewed on July 21, 2009). "School of Electrical Engineering and Computer Science." Includes bibliographical references (p. 113-117).

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Costantino, Gianpiero. "Enforcing trust, collaboration and power-saving in MANETs." Thesis, Università degli Studi di Catania, 2011. http://hdl.handle.net/10761/184.

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Nowadays mobile data communications are becoming more and more popular and, at same time, people routinely carry along the last generation of mobile devices, called Smartphones. In particular, the ability to connect directly to other similar devices makes smartphones very powerful. The field that we are going to explore is that of Mobile Ad hoc Networks (MANETs). In a network without infrastructure, devices are connected directly or by means of others and this makes collaboration fundamental even though the behaviour, that is, the collaborative attitude of each participant. To provide a more transparent system, we present a mechanism in which a device, through observation of a neighbour, is able to establish the reputation of that neighbour. Afterwards, that value for each node is scattered across the network by means of special packets called Recommendations. Values of reputation obtained with the previous mechanism are parameters of judgement for a Quality of Service (QoS) technique used in communications. Indeed, devices with a bad reputation are strongly penalised when they require a service to others. In particular, the penalisation that a node gets depends on its contribution of collaboration: the less is the collaboration the more is the penalisation. Finally, we focus our research on power-saving. By introducing a novel protocol to cover a weakness of the Dynamic Source Routing (DSR), each device becomes capable of preserving its own energy especially during long and repetitive communications. All prototypes designed in this thesis were implemented and simulated through the Network Simulator 2 (NS2).

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Anwar, Khurshid, and Asad Khan. "AC and QAR for Provisioning of QoS in MANETs." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4787.

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Mobile Ad-hoc network (MANET) is a collection of mobile nodes which communicate over wireless channels without any centralized control or existing infrastructure. The freely movement of nodes allow them to join or leave the network independently. Due to node mobility, wireless channels and limited resources makes the provision of Quality of Services (QoS) in MANETs very challenging. With the emerging use of multimedia applications over MANETs which requires different types of QoS provision from the networks. The Admission Control (AC) and QoS-Aware routing (QAR) protocols have made a progress in provision of QoS up to some extents. In this thesis, various AC and QAR protocols are reviewed and their characteristics and limitations are identified. We also make a comparison between DSR and AODV routing protocols in different network scenarios.
The literature study shows that the performance of network layer best-effort protocols has been improved with the use of QAR and AC protocols to sustain the QoS requirements of the applications. In current literature AC and QAR protocols are satisfying single metric of QoS. At the same time different applications such as multimedia applications which require various types of assurance from the network on the Quality of services (QoS) The simulation results show that DSR performance is better than AODV when we have less traffic load.

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Chen, Lei Lee Chung-wei. "On secure media streaming with path diversity in MANETs." Auburn, Ala., 2007. http://repo.lib.auburn.edu/Send%2002-04-08/CHEN_LEI_20.pdf.

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20

Abbas, Sohail. "A layered security approach for cooperation enforcement in MANETs." Thesis, Liverpool John Moores University, 2011. http://researchonline.ljmu.ac.uk/6091/.

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In fully self-organized MANETs, nodes are naturally reluctant to spend their precious resources forwarding other nodes' packets and are therefore liable to exhibit selfish or sometimes malicious behaviour. This selfishness could potentially lead to network partitioning and network performance degradation. Cooperation enforcement schemes, such as reputation and trust based schemes have been proposed to counteract the issue of selfishness. The sole purpose of these schemes is to ensure selfish nodes bear the consequences of their bad actions. However, malicious nodes can exploit mobility and free identities available to breach the security of these systems and escape punishment or detection. Firstly, in the case of mobility, a malicious node can gain benefit even after having been detected by a reputation-based system, by interacting directly with its source or destination nodes. Secondly, since the lack of infrastructure in MANETs does not suit centralized identity management or centralized Trusted Third Parties, nodes can create zero-cost identities without any restrictions. As a result, a selfish node can easily escape the consequences of whatever misbehaviour it has performed by simply changing identity to clear all its bad history, known as whitewashing. Hence, this makes it difficult to hold malicious nodes accountable for their actions. Finally, a malicious node can concurrently create and control more than one virtual identity to launch an attack, called a Sybil attack. In the context of reputation-based schemes, a Sybil attacker can disrupt the detection accuracy by defaming other good nodes, self-promoting itself or exchanging bogus positive recommendations about one of its quarantined identities. This thesis explores two aspects of direct interactions (DIs), i. e. Dis as a selfish nodes' strategy and Dis produced by inappropriate simulation parameters. In the latter case DIs cause confusion in the results evaluation of reputation-based schemes. We propose a method that uses the service contribution and consumption information to discourage selfish nodes that try to increase their benefit through DIs. We also propose methods that categorize nodes' benefits in order to mitigate the confusion caused in the results evaluation. A novel layered security approach is proposed using proactive and reactive paradigms to counteract whitewashing and Sybil attacks. The proactive paradigm is aimed at removing the advantages that whitewashing can provide by enforcing a non-monetary entry fee per new identity, in the form of cooperation in the network. The results show that this method deters these attackers by reducing their benefits in the network. In the reactive case, we propose a lightweight approach to detect new identities of whitewashers and Sybil attackers on the MAC layer using the 802.11 protocol without using any extra hardware. The experiments show that a signal strength based threshold exists which can help us detect Sybil and whitewashers' identities. Through the help of extensive simulations and real-world testbed experimentations, we are able to demonstrate that our proposed solution detects Sybil or whitewashers' new identities with good accuracy and reduces the benefits of malicious activity even in the presence of mobility.

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Lu, Bin. "Quality of Service (QoS) security in mobile ad hoc networks." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4295.

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With the rapid proliferation of wireless networks and mobile computing applications, Quality of Service (QoS) for mobile ad hoc networks (MANETs) has received increased attention. Security is a critical aspect of QoS provisioning in the MANET environment. Without protection from a security mechanism, attacks on QoS signaling system could result in QoS routing malfunction, interference of resource reservation, or even failure of QoS provision. Due to the characteristics of the MANETs, such as rapid topology change and limited communication and computation capacity, the conventional security measures cannot be applied and new security techniques are necessary. However, little research has been done on this topic. In this dissertation, the security issues will be addressed for MANET QoS systems. The major contributions of this research are: (a) design of an authentication mechanism for ad hoc networks; (b) design of a security mechanism to prevent and detect attacks on the QoS signaling system; (c) design of an intrusion detection mechanism for bandwidth reservation to detect QoS attacks and Denial of Service (DoS) attacks. These three mechanisms are evaluated through simulation.

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Fountanas, Leonidas. "Active queue management mechanisms for real-time traffic in MANETs /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA401102.

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Thesis (Electrical Engineer and M.S. in Electrical Engineering) Naval Postgraduate School, Dec. 2001.
"December 2001." Thesis advisor(s): Tummala, Murali ; Ives, Robert W. ; Parker, Robert E. Includes bibliographical references (p. 101-104). Also available online.

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Silva, Eduardo da. "Gerenciamento de chaves públicas sobrevivente baseado em grupos para MANETS." reponame:Repositório Institucional da UFPR, 2009. http://hdl.handle.net/1884/21250.

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24

Asif, Muhammad. "Flow aware admission control protocol for QoS provisioning in MANETs." Thesis, University of Surrey, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.560502.

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In Mobile Ad hoc Networks (MANETs), mobile nodes communicate over an error prone wireless channel without any centralized control. MANETs have n9 fixed topology because mobile nodes can freely join or leave the network at any time. As a consequence, it is difficult to guarantee Quality of Service (QoS) in these networks. The current routing , protocols provide only best effort services to the applications. Multimedia communications become very popular and require various types of QoS guarantee from the network such as guranteed throughput, bounded end-to-end delay. The QoS-aware routing (QA) and Admission Control (AC) protocols try to address the issue of QoS to some extent. In this work, a novel Flow Aware Admission Control (FAAC) protocol is designed to assure the guaranteed throughput to data sessions. It utilizes the route cache of routing protocol and devises a new admission technique to accept or reject data session to the network. It is partially coupled with the Oynamic Source Routing (OSR) protocol as it has used the basic functionality of route search of the OSR protocol. The protocol has two phases: (i) route discovery and (ii) test the route nodes resources for a data session entry. The performance evaluations show that the protocol outperforms the existing best effort routing and QAR and AC protocols such as OSR and Contention Aware Admission Control (CACP) protocols in providing QoS in MANETs. Mobility is a big challenge to assure guaranteed throughput to data sessions. To address this issue, we have designed F AAC-Multipath protocol that uses multiple routes for data transmission. The protocol maintains two tested routes for each data session and devises new fast switching mechanisms that switch the data flow from one route to another to guarantee the throughput. Multimedia applications require guaranteed throughput as well as bounded end-to-end delay. To address this issue we.have designed Flow Aware Admission Control-Multipath with Multiple constraints (F AAC-MM). This protocol assures the application with guaranteed throughput as well as bounded end-to-end delay. FAAC-MM switches the data flow from primary to secondary route on the basis of achieved throughput and end-to-end delay. We have also analyzed and compared the proposed protocols with the state of the art protocols such as CACP and Multi-path for Mobile Ad Hoc Networks. The simulation results show that our protocol outperforms the above mentioned protocols.

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Fountanas, Leonidas, and Leonidas Fountanas. "Active queue management mechanisms for real-time traffic in MANETs." Thesis, Monterey, California. Naval Postgraduate School, 2001. http://hdl.handle.net/10945/6052.

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Approved for public release; distribution is unlimited.
Approved for public release; distribution is unlimited.
This thesis develops active queue management mechanisms for real-time traffic for MANETs. Providing QoS for real-time applications is still an open issue as stated in RFC 2309. The proposed packet-dropping algorithm called Selective Early Discard (SED) selectively drops packets in order to spread the packet losses in a queue. Two variations of SED are also examined: one adds priority in order to provide service differentiation and the other utilizes timestamps to enable the intermediate nodes to drop packets that are likely to be unusable by the receiver due to excessive delay. Another scheme that drops bits instead of packets is also investigated. Using simulation, the new queuing schemes are evaluated in a MANET environment, and their performance is compared with other existing QoS schemes, such as Random Early Discard (RED) and First In First Out (FIFO). Results indicate that SED minimizes the burst errors due to buffer overflow, thereby improving the performance for real-time traffic. SED is also capable of providing service differentiation; additional performance improvement can be realized by utilizing timestamps. Bit-dropping techniques can provide further performance improvements by spreading the error at the bit level (versus spreading the error at the packet level as in SED).
This thesis develops active queue management mechanisms for real-time traffic for MANETs. Providing QoS for real-time applications is still an open issue as stated in RFC 2309. The proposed packet-dropping algorithm called Selective Early Discard (SED) selectively drops packets in order to spread the packet losses in a queue. Two variations of SED are also examined: one adds priority in order to provide service differentiation and the other utilizes timestamps to enable the intermediate nodes to drop packets that are likely to be unusable by the receiver due to excessive delay. Another scheme that drops bits instead of packets is also investigated. Using simulation, the new queuing schemes are evaluated in a MANET environment, and their performance is compared with other existing QoS schemes, such as Random Early Discard (RED) and First In First Out (FIFO). Results indicate that SED minimizes the burst errors due to buffer overflow, thereby improving the performance for real-time traffic. SED is also capable of providing service differentiation; additional performance improvement can be realized by utilizing timestamps. Bit-dropping techniques can provide further performance improvements by spreading the error at the bit level (versus spreading the error at the packet level as in SED).

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Tachtatzis, Christos. "Load distribution and energy awareness in manets using multipath routing." Thesis, University of Strathclyde, 2008. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21972.

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Wireless ad-hoc networks are characterised by lack of infrastructure and frequent topological changes. Traditional routing protocols seek only single paths to the desired destinations, while multipath routing obtains multiple paths for only marginal additional overhead. This work argues that multipath routing is advantageous, even allowing for the additional overheads, because of the improved network load distribution. The merits of multipath routing are shown through extensive performance evaluation considering packet delivery ratio, average end-to-end delay and routing efficiency, for both mobile and static scenarios. The second aspect of the thesis addresses energy awareness. When a single connection is considered, multipath routing can potentially consume more total energy compared to its unipath counterparts because some traffic can traverse longer (in terms of hop count) paths. On the other hand, unipath routing concentrates nodal traffic over the same single path; resulting in unfairness for the intermediate hops and uneven energy consumption which, in turn, can result in network partitioning. Here, it is argued that multipath routing extends the network lifetime, because the routing protocol can make more sophisticated decisions to avoid node exhaustion. Two novel energy aware routing schemes, which select optimal paths to homogenise the energy map of the network, are presented. A range of performance evaluation techniques are employed to demonstrate the merits of the proposed schemes, and it is shown that the approach of homogenising the network energy map mitigates against the effects of inevitable node outages cause by energy exhaustion and prolongs network lifetime.

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Abdulai, Jamal-deen. "Probabilistic route discovery for Wireless Mobile Ad Hoc Networks (MANETs)." Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/719/.

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Mobile wireless ad hoc networks (MANETs) have become of increasing interest in view of their promise to extend connectivity beyond traditional fixed infrastructure networks. In MANETs, the task of routing is distributed among network nodes which act as both end points and routers in a wireless multi-hop network environment. To discover a route to a specific destination node, existing on-demand routing protocols employ a broadcast scheme referred to as simple flooding whereby a route request packet (RREQ) originating from a source node is blindly disseminated to the rest of the network nodes. This can lead to excessive redundant retransmissions, causing high channel contention and packet collisions in the network, a phenomenon called a broadcast storm. To reduce the deleterious impact of flooding RREQ packets, a number of route discovery algorithms have been suggested over the past few years based on, for example, location, zoning or clustering. Most such approaches however involve considerably increased complexity requiring additional hardware or the maintenance of complex state information. This research argues that such requirements can be largely alleviated without sacrificing performance gains through the use of probabilistic broadcast methods, where an intermediate node rebroadcasts RREQ packets based on some suitable forwarding probability rather than in the traditional deterministic manner. Although several probabilistic broadcast algorithms have been suggested for MANETs in the past, most of these have focused on “pure” broadcast scenarios with relatively little investigation of the performance impact on specific applications such as route discovery. As a consequence, there has been so far very little study of the performance of probabilistic route discovery applied to the well-established MANET routing protocols. In an effort to fill this gap, the first part of this thesis evaluates the performance of the routing protocols Ad hoc On demand Distance Vector (AODV) and Dynamic Source Routing (DSR) augmented with probabilistic route discovery, taking into account parameters such as network density, traffic density and nodal mobility. The results reveal encouraging benefits in overall routing control overhead but also show that network operating conditions have a critical impact on the optimality of the forwarding probabilities. In most existing probabilistic broadcast algorithms, including the one used here for preliminary investigations, each forwarding node is allowed to rebroadcast a received packet with a fixed forwarding probability regardless of its relative location with respect to the locations of the source and destination pairs. However, in a route discovery operation, if the location of the destination node is known, the dissemination of the RREQ packets can be directed towards this location. Motivated by this, the second part of the research proposes a probabilistic route discovery approach that aims to reduce further the routing overhead by limiting the dissemination of the RREQ packets towards the anticipated location of the destination. This approach combines elements of the fixed probabilistic and flooding-based route discovery approaches. The results indicate that in a relatively dense network, these combined effects can reduce the routing overhead very significantly when compared with that of the fixed probabilistic route discovery. Typically in a MANET there are regions of varying node density. Under such conditions, fixed probabilistic route discovery can suffer from a degree of inflexibility, since every node is assigned the same forwarding probability regardless of local conditions. Ideally, the forwarding probability should be high for a node located in a sparse region of the network while relatively lower for a node located in a denser region of the network. As a result, it can be helpful to identify and categorise mobile nodes in the various regions of the network and appropriately adjust their forwarding probabilities. To this end the research examines probabilistic route discovery methods that dynamically adjust the forwarding probability at a node, based on local node density, which is estimated using number of neighbours as a parameter. Results from this study return significantly superior performance measures compared with fixed probabilistic variants. Although the probabilistic route discovery methods suggested above can significantly reduce the routing control overhead without degrading the overall network throughput, there remains the problem of how to select efficiently forwarding probabilities that will optimize the performance of a broadcast under any given conditions. In an attempt to address this issue, the final part of this thesis proposes and evaluates the feasibility of a node estimating its own forwarding probability dynamically based on locally collected information. The technique examined involves each node piggybacking a list of its 1-hop neighbours in its transmitted RREQ packets. Based on this list, relay nodes can determine the number of neighbours that have been already covered by a broadcast and thus compute the forwarding probabilities most suited to individual circumstances.

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Al-Qassas, Raad S. "On the performance of traffic-aware reactive routing in MANETs." Thesis, University of Glasgow, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443330.

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Chagantipati, Raj K. "A theoretical study on mobility and path duration estimate in manets." Thesis, Wichita State University, 2010. http://hdl.handle.net/10057/3712.

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A Mobile Ad hoc Network (MANET) is a collection of mobile nodes that operate without any backbone infrastructure support. Implementation of MANETS is very useful in certain military applications and during emergency situations such as earth quakes and re accidents. In MANETS, routing decisions are governed by the operating routing protocol. Mobility is one of the most important factors to be considered in developing such routing protocols. The e ect of mobility on a network is quanti ed in terms of link and route duration times. Therefore, understanding mobility and its e ect on path duration will de nitely help in coming up with a better routing algorithm. In this thesis, we discuss the importance of mobility and its impact on a network. Also, we tried to come up with an enhanced version of the mathematical model for the path duration estimate from an existing model. One application of the path duration estimate is to select a route with maximum expiry time unlike most of the routing algorithms which choose a path based on shortest path. First, we estimate route expiry time with a single relay node between the source and the destination. With this simple scenario, we analyze how long it takes for a relay node to come out of the transmission range of the source node. Then, we generalize the analysis for h number of hops used to reach destination. Also, the e ect on path duration due to parameters such as transmission range, node mobility, relative velocity, and number of hops in the route is studied. Simulations are performed in MATLAB and the signi cance of the proposed model is discussed with an analysis of the results obtained.
Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science

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Kiourktsidis, Ilias. "Flexible cross layer design for improved quality of service in MANETs." Thesis, Brunel University, 2011. http://bura.brunel.ac.uk/handle/2438/7464.

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Mobile Ad hoc Networks (MANETs) are becoming increasingly important because of their unique characteristics of connectivity. Several delay sensitive applications are starting to appear in these kinds of networks. Therefore, an issue in concern is to guarantee Quality of Service (QoS) in such constantly changing communication environment. The classical QoS aware solutions that have been used till now in the wired and infrastructure wireless networks are unable to achieve the necessary performance in the MANETs. The specialized protocols designed for multihop ad hoc networks offer basic connectivity with limited delay awareness and the mobility factor in the MANETs makes them even more unsuitable for use. Several protocols and solutions have been emerging in almost every layer in the protocol stack. The majority of the research efforts agree on the fact that in such dynamic environment in order to optimize the performance of the protocols, there is the need for additional information about the status of the network to be available. Hence, many cross layer design approaches appeared in the scene. Cross layer design has major advantages and the necessity to utilize such a design is definite. However, cross layer design conceals risks like architecture instability and design inflexibility. The aggressive use of cross layer design results in excessive increase of the cost of deployment and complicates both maintenance and upgrade of the network. The use of autonomous protocols like bio-inspired mechanisms and algorithms that are resilient on cross layer information unavailability, are able to reduce the dependence on cross layer design. In addition, properties like the prediction of the dynamic conditions and the adaptation to them are quite important characteristics. The design of a routing decision algorithm based on Bayesian Inference for the prediction of the path quality is proposed here. The accurate prediction capabilities and the efficient use of the plethora of cross layer information are presented. Furthermore, an adaptive mechanism based on the Genetic Algorithm (GA) is used to control the flow of the data in the transport layer. The aforementioned flow control mechanism inherits GA’s optimization capabilities without the need of knowing any details about the network conditions, thus, reducing the cross layer information dependence. Finally, is illustrated how Bayesian Inference can be used to suggest configuration parameter values to the other protocols in different layers in order to improve their performance.

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Said, Aicha. "Routing protocols performance and intelligent quality of service applied to MANETs." Thesis, Sheffield Hallam University, 2008. http://shura.shu.ac.uk/20310/.

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The wireless revolution prompted by the success of IEEE 802.11 standard has pressed the research community to deal with requirements of new wireless networks. In particular, wireless ad-hoc networks which are, specifically, a collection of wireless mobile nodes dynamically forming a temporary network without the use of any preexisting infrastructure or centralised administration. Routing protocols used in ad-hoc networks must automatically and continually adjust to environments. Most emerging network services require specialised Quality-of-Service (QoS) functionalities that cannot be provided by the current QoS-unaware routing protocols. Despite the large amount of research in these areas, several issues still need further investigation. The following points have become main concerns: i) traditional use of the hop count metric does not capture the very nature of wireless paths, resulting in poor performance of wireless networks; ii) the lack of comprehensive simulation methods to effectively observed performance of networks in various conditions and iii) the complexity of multi-constraint routing decisions, resulting in poor service quality in the end-user's point of view. This study takes an experimental approach to the evaluation of ad-hoc routing protocols and focuses on routing parameters as well as multimedia application QoS performance. In this thesis, we tackle the above mentioned issues and implement an efficient solution for the multi-constraint problem based on network measurements of valid experiments set-up. This study is exclusively based on simulations using NS-2 network simulator. In order to obtain an overview of the limitations of current conventional routing protocols, AODV and DSR protocols are used and their limitations in terms of QoS are measured and discussed. Operating conditions vary greatly from a static, lightly loaded network to constantly moving nodes with up to 10 simultaneous transmission connections. The results show that network performance degrades quickly and that QoS requirement was hardly met by any of these protocols. To evaluate the overall network performance, a new fuzzy logic assessment approach was developed taking into account the QoS parameters requirement of the transmitted application. Critical parameters were obtained through detailed simulation experiments under demanding operating conditions. These parameters were used as input to the fuzzy logic system to allow the computation of a single metric to represent the input variables (i.e. delay, jitter and throughput). The end results show that without a complicated mathematical model, a QoS value can be computed. This study addresses both theoretical aspects of QoS performance and routing progress in ad-hoc networks as well as practical issues in the set-up of simulation based studies. Finally, this study indicated that intelligent techniques can be effective for processing multiple QoS metrics to obtain an overall parameter that represents the application QoS. They can be adapted, not only to QoS routing, but to various aspects of QoS provisioning techniques.

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Schomp, Kyle Graham. "Dynamic TCP Proxies: Coping with Mobility and Disadvantaged Hosts in MANETs." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1278687374.

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Vaddhireddy, Jyothirmye. "A Novel Swarm Intelligence based IWD Algorithm for Routing in MANETs." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1321589580.

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Kioumourtzis, Georgios A. "Simulation and evaluation of routing protocols for Mobile Ad Hoc Networks (MANETs)." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Sep%5FKioumourtzis.pdf.

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Thesis (M.S. in Systems Engineering and M.S. in Computer Science)--Naval Postgraduate School, September 2005.
Thesis Advisor(s): Gilbert M. Lundy, Rex Buddenberg. Includes bibliographical references (p.133-135). Also available online.

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Baggio, Miguel Angelo. "ATENTO: UM DETECTOR DE DEFEITOS PARA MANETS BASEADO NA POTÊNCIA DO SINAL." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/5373.

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Fault detector is an essential component in building reliable distributed systems and its design depends heavily on the model of distributed system, which has demanded several solutions to address the movement of nodes. This dissertation presents a gossip-based unreliable failure detector for mobile ad hoc networks (MANETs) that uses the intensity of received signal to differ faulty nodes from mobile nodes. The differentiation is done by maintaining information on the intensity measurement signal reception in the nodes of the system in a small historic regions. This work also presents a simulator for mobile wireless networks where is possible configure simulations messaging with pre-determined movements of the nodes in the network. The simulator provides the signal strength received in a message, and allows configuration simulate various aspects such as frequency and intensity transmission of a message. The failure detector presented in this work provides a new method that uses more than one rule for deciding to suspect a node. Surveys show improvements in service quality of the detector compared with the traditional gossip algorithm.
Detectar falhas é uma tarefa essencial na construção de sistemas distribuídos confiáveis e seu projeto depende fortemente do modelo de sistema distribuído. Diversas soluções tem sido desenvolvidas para tratar a movimentação de nodos em sistemas distribuídos. Este trabalho apresenta um novo detector de defeitos assíncrono não-confiável para redes móveis ad hoc (MANETs). Nodos falhos são diferenciados de nodos móveis através da manutenção de informação sobre a medida de potência do sinal de recepção nos nodos do sistema em um pequeno histórico de regiões. Neste trabalho também foi desenvolvido um simulador para redes móveis sem fio onde é possível configurar simulações de transmissão de mensagens com movimentos prédeterminados dos nodos na rede. O simulador disponibiliza a potência do sinal recebido em uma mensagem, e permite que sejam configurados diversos aspectos da simulação como freqüência e potência de transmissão de uma mensagem. O detector de defeitos proposto neste trabalho utiliza um método para suspeitar de um nodo que está dentro de sua região de alcance de transmissão e outro método para um nodo que está movimentando-se para fora do seu alcance de transmissão. Avaliações apresentadas neste trabalho demonstram que é possível uma redução no tempo de detecção de uma falha e um menor número de falsas suspeitas, quando comparados com detectores que utilizam apenas gossip.

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Osathanunkul, Kitisak. "A cross-layer and multi-metric routing decision making framework for MANETs." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/a-crosslayer-and-multimetric-routing-decision-making-framework-for-manets(747a6389-d354-4afc-8810-c4e781662107).html.

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Mobile Ad hoc Networks (MANETs) are re-emerging as a popular networking facility for wireless device users. A growing number of diversified applications are now accessible via wireless devices. The different applications may have different Quality of Service (QoS) requirements, which may better be satisfied by using different routing methods or metric types. Existing ad hoc network routing solutions do not consider various application-level requirements when making a routing decision. They typically make routing decisions based upon limited information acquired at the network layer. Most of the existing routing protocols make use of a single routing metric. Using a single metric type and/or information, only acquired at the network layer may not be able to accommodate different QoS requirements, imposed by diversified user-level applications or application-level data types.The aim of this thesis is to design an efficient routing function for ad hoc networks while at the same time satisfying users‟ and/or applications‟ QoS and security requirements. To achieve this, the thesis investigates and specifies routing requirements that could best support application-level QoS and security requirements in MANETs. It also investigates and critically analyses the state of the art in MANET routing, and the mechanisms used for protecting the routing functions. To overcome the weaknesses and advance the state of the art in MANET routing, this thesis proposes two major solutions. The first solution is the Secure ETX (SETX) routing protocol. It is a secure routing solution that can provide routing functions efficiently in malicious MANET environment. The SETX protocol provides a security mechanism to counter black hole attacks in MANETs on the ETX metric acquisition process. Simulation studies have been carried out and discussed in the thesis. Simulation results show that the SETX protocol can provide a marked improvement in network performances in the presence of black hole attacks, and it can do so with a negligible level of additional overhead.The second solution is a novel routing decision making called the Flexible Routing Decision (FRD) framework. The FRD framework supports routing decision making by using multiple metric types (i.e. multi-criteria routing decision making) and uses a cross-layer approach to support application-level QoS requirements. This allows users to use different routing metrics types, making the most appropriate routing decision for a given application. To accommodate the diversified application-level QoS requirements, multiple routing metric types have been identified and interpreted in the FRD framework design. The FRD framework has overcome some weaknesses exhibited by existing single metric routing decision making, used in MANETs. The performance of a routing decision making of FRD is also evaluated using NS2 simulation package. Simulation results demonstrate that the FRD framework outperforms the existing routing decision making methods.

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Barros, Urlan Salgado de. "Um sistema baseado na Teoria do Perigo para detectar ataques Jamming em Manets." reponame:Repositório Institucional da UFPR, 2013. http://hdl.handle.net/1884/32220.

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Resumo: As redes sem fio possibilitam a comunica¸c˜ao de dispositivos computacionais port´ateis, como celulares, notebooks, palmtops, entre outros. Um principal desafio `a seguran¸ca das aplica¸c˜oes e servi¸cos dependentes das redes sem fio ´e a vulnerabilidade das comunica¸c˜oes aos ataques jamming. No escopo das redes sem fio, as redes m´oveis ad hoc (MANETs - Mobile Ad hoc Networks) permitem que os usu´arios tenham mobilidade e acessem as informa¸c˜oes de forma descentralizada empregando ondas eletromagn´eticas atrav´es do meio de transmiss˜ao sem fio. Para tentar garantir a existˆencia de uma MANET segura, robusta e confi´avel, ´e necess´ario desenvolver um sistema de detec¸c˜ao como contramedida inicial aos ataques jamming. Em face `as limita¸c˜oes dos sistemas de detec¸c˜ao de ataques jamming existentes, este trabalho prop˜oe um sistema de detec¸c˜ao distribu´?do e flex´?vel contra ataques jamming em MANETs. O sistema de detec¸c˜ao proposto, denominado DANTE (do inglˆes, Detecting jAmming attacks by the daNger ThEory), tem como inspira¸c˜ao a teoria do perigo, a qual possui caracter´?sticas que inspiram o desenvolvimento de um sistema de detec¸c˜ao de ataques jamming nas MANETs, como a descentraliza¸c˜ao, a dinamicidade e a quantifica ¸c˜ao. O sistema DANTE ´e composto por uma arquitetura com trˆes m´odulos, denominados medi¸c˜oes e informa¸c˜oes, detec¸c˜ao bio-inspirada e resposta ao ataque jamming. O m´odulo de medi¸c˜oes e informa¸c˜oes calcula os valores das medi¸c˜oes estat´?sticas e coleta os dados provenientes da camada de enlace que sofreram interferˆencia. O m´odulo de detec ¸c˜ao bio-inspirada determina e quantifica os ataques na rede. O m´odulo de resposta ao ataque jamming toma uma a¸c˜ao apropriada de acordo com a quantifica¸c˜ao do ataque. Para avaliar o desempenho do sistema DANTE s˜ao empregados dois tipos diferentes de cen´arios. Os cen´arios s˜ao compostos por trˆes dispositivos, os quais dois deles s˜ao leg´?timos e um atua como o atacante. No primeiro cen´ario, os dispositivos s˜ao vizinhos entre si, j´a no segundo cen´ario, o dispositivo atacante ´e vizinho somente de um dispositivo leg´?timo. A fim de avaliar o sistema DANTE s˜ao empregadas as m´etricas de desempenho denominadas acur´acia e precis˜ao. Al´em disso, o sistema DANTE ´e comparado a um outro sistema de detec¸c˜ao de ataques jamming encontrado na literatura, denominado neste trabalho como CLADE. Os resultados de simula¸c˜ao mostram que o sistema DANTE possui um desempenho superior ao sistema CLADE. Al´em de obter a precis˜ao de 100% nos ataques jamming deceptivo e reativo, o sistema DANTE alcan¸cou os maiores resultados para a acur´acia nos ataques jamming deceptivo, aleat´orio e reativo.

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38

Mohammad, Nazeeruddin. "Integrated host auto-configuration, name resolution and service discovery protocols for dynamic MANETs." Thesis, Ulster University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529579.

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39

Pease, Sarogini G. "A cross-layer middleware architecture for time and safety critical applications in MANETs." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13606.

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Mobile Ad hoc Networks (MANETs) can be deployed instantaneously and adaptively, making them highly suitable to military, medical and disaster-response scenarios. Using real-time applications for provision of instantaneous and dependable communications, media streaming, and device control in these scenarios is a growing research field. Realising timing requirements in packet delivery is essential to safety-critical real-time applications that are both delay- and loss-sensitive. Safety of these applications is compromised by packet loss, both on the network and by the applications themselves that will drop packets exceeding delay bounds. However, the provision of this required Quality of Service (QoS) must overcome issues relating to the lack of reliable existing infrastructure, conservation of safety-certified functionality. It must also overcome issues relating to the layer-2 dynamics with causal factors including hidden transmitters and fading channels. This thesis proposes that bounded maximum delay and safety-critical application support can be achieved by using cross-layer middleware. Such an approach benefits from the use of established protocols without requiring modifications to safety-certified ones. This research proposes ROAM: a novel, adaptive and scalable cross-layer Real-time Optimising Ad hoc Middleware framework for the provision and maintenance of performance guarantees in self-configuring MANETs. The ROAM framework is designed to be scalable to new optimisers and MANET protocols and requires no modifications of protocol functionality. Four original contributions are proposed: (1) ROAM, a middleware entity abstracts information from the protocol stack using application programming interfaces (APIs) and that implements optimisers to monitor and autonomously tune conditions at protocol layers in response to dynamic network conditions. The cross-layer approach is MANET protocol generic, using minimal imposition on the protocol stack, without protocol modification requirements. (2) A horizontal handoff optimiser that responds to time-varying link quality to ensure optimal and most robust channel usage. (3) A distributed contention reduction optimiser that reduces channel contention and related delay, in response to detection of the presence of a hidden transmitter. (4) A feasibility evaluation of the ROAM architecture to bound maximum delay and jitter in a comprehensive range of ns2-MIRACLE simulation scenarios that demonstrate independence from the key causes of network dynamics: application setting and MANET configuration; including mobility or topology. Experimental results show that ROAM can constrain end-to-end delay, jitter and packet loss, to support real-time applications with critical timing requirements.

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QUENTAL, Nivia Cruz. "Um sistema de disseminação de pieces para a melhoria do desempenho de aplicações bittorrent sobre manets." Universidade Federal de Pernambuco, 2009. https://repositorio.ufpe.br/handle/123456789/1969.

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Made available in DSpace on 2014-06-12T15:53:32Z (GMT). No. of bitstreams: 2 arquivo1922_1.pdf: 1019141 bytes, checksum: fd41612907761997292dae2b897da5b2 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009
As redes ad hoc sem fio ou MANETs são conhecidas pela sua flexibilidade e independência de uma infraestrutura para coordenação de nós. A quantidade de aplicações apoiadas nesta arquitetura tem aumentado vertiginosamente nos últimos anos dado que operações de resgate, aplicações de conferências e de compartilhamento de arquivos encontraram nestas redes um ambiente favorável ao seu desenvolvimento. Estas aplicações emergentes executadas no topo das MANETs funcionam em uma lógica peer-to-peer, uma vez que os peers da rede executam a mesma função e repassam informações seguindo algoritmos de roteamento no nível aplicação. Além disso, uma MANET compartilha vários pontos em comum com uma rede P2P, entre eles a descentraliza ção e a flexibilidade mediante a entrada e sa´ıda de nós. Desta forma, entende-se que as aplicações desenvolvidas para MANETs podem ser inspiradas nos protocolos P2P utilizados com sucesso na Internet. Entretanto, as MANETs possuem uma natureza bastante diversa da Internet, uma vez que oferecem novos desafios, como a mobilidade dos nós e as limitações na largura de banda. Estes fatores levam ao fraco desempenho das aplicações P2P nesta arquitetura, em comparação ao desempenho das mesmas na Internet. Assim, melhorias destes protocolos destinadas ao ambiente sem fio se fazem necessárias. Esta dissertação propõe um Sistema de Disseminação para otimização do protocolo BitTorrent no ambiente de MANETs. O sistema proposto consiste em estratégias espec íficas para disseminação de conteúdo e em uma interface que permite que algumas mensagens de PIECE do BitTorrent sejam entregues no modo broadcast, tirando proveito da natureza difusora do meio de comunicação sem fio. O desempenho do BitTorrent tradicional e de sua versão melhorada com o Sistema

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Harding, Christopher A. "Development of a Delay Algorithm and a Co-Simulation Framework for NCS over MANETs." Thesis, Staffordshire University, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.522128.

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Bakhsh, Helen Jameel H. "ATL-QoS : an adaptive trust-aware location-based framework for achieving QoS in MANETs." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/atlqos-an-adaptive-trustaware-locationbased-framework-for-achieving-qos-in-manets(d0c5f89e-5576-4a91-a601-aa4aca60e15a).html.

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Mobile ad hoc networks (MANETs) have gained increasing attention from industry for their potential applications. MANETs allow devices to communicate in areas with no pre-existing communication infrastructure. In MANETs, node mobility leads to dynamic changes in network topologies and fluctuations in network available bandwidth. The lack of infrastructural support means that communication nodes need to collaborate among themselves functioning as routers (intermediate nodes) for other nodes. This places additional processing and communication loads onto the communication nodes and opens up doors to more active attacks by intermediate nodes. It is also worth noting that mobile nodes are typically battery powered, and they are more restrictive in terms of storage space and processing capabilities than their wired counterpart. These MANET features indicate that achieving QoS in MANETs should be done in the most cost-effective manner. In this thesis, a novel Adaptive Trust-aware Location-based (ATL-QoS) framework is proposed. The ATL-QoS framework can harvest fluctuating available bandwidth in the underlying network to deliver high priority traffic in various network conditions. The novelty of the framework lies in that it uses single path and multiple path deliveries and packet duplication over multiple path, in an adaptive manner, in an attempt to increase high priority traffic delivery with minimum bandwidth overhead costs. The framework handles low and high priority traffic in a differential manner. To implement these ideas, two novel ATL-QoS components are designed: (1) a Trust-Aware Dynamic Location-based (improved version) (TADLV2) multiple path discovery protocol and (2) a path Selection, traffic Allocation, and path Verification (SAV) solution. The TADLV2 protocol is designed to discover multiple path between a pair of communication nodes with minimum bandwidth overheads, we first designed TADL protocol and then an improved version of TADL, TADLV2. The SAV solution is designed to increase high priority traffic delivery success. These ATL-QoS framework ideas are implemented and evaluated using the NS-2 simulation and compared against the most relevant protocol in the literature. The simulation study shows that ATL-QoS outperforms the relevant protocol in terms of reducing routing overheads and increasing packet delivery ratios. These enhancements making ATL-QoS more effective in providing QoS.

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Srikanth, Bathi. "Detecting Selfish Nodes in MANETs." Thesis, 2014. http://ethesis.nitrkl.ac.in/6047/1/212CS1098-7.pdf.

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Mobile Ad-hoc Networks(MANETs) is a self configured and decentralized wireless network without any prior infrastructure. Every node in it acts as a router as well as end-system and hence each node in MANET is allowed to move freely which makes routing difficult. Most of the MANET routing algorithms like AODV and DSR assumes that every node will forward every packet it receives. Source node will relay packets to the destination node through the intermediate nodes. However, misbehaviour of the selfish nodes is a common phenomenon in MANET. These nodes use the network and its services and do not provide any services to intermediate nodes in order to save energy such as battery, CPU power and bandwidth for relaying data from other nodes and reserve for themselves. These selfish nodes will degrade the performances of wireless ad hoc networks. However, we can identify the selfish nodes by modifying the original AODV and DSR routing algorithms. In this thesis, we proposed a time based scheme for identifying selfish nodes and perform the simulation using Network Simulator 2.34.

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Leu, Seiven, and 呂西文. "Solving Broadcast Storm Problems in MANETs." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/8w677p.

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博士
國立東華大學
資訊工程學系
100
In recent years, mobile devices are becoming popular and high-speed wireless communication is up roaring. In a wireless network environment, mobile ad hoc network (MANET) has gained a lot of attention due to its self-organizing and infrastructure-free characteristics. Unlike the traditional wireless networks, each node in MANET can act as a router to receive and forward packets. All nodes transmit packets by multi-hop in MANET. Hence, MANET is very convenient and flexible. The topology of MANET can be deployed easily with few restrictions. Although the topology of MANET can be deployed easily with few restrictions, the maintenance faces great challenges. All nodes can randomly move around, leave the network or switch off. Hence, broadcasting has been used widely in diffusing data, routing or topology information in MANET. Unfortunately, MANET may be filled with a large number of redundant broadcasting packets. Furthermore, in order to transmit the broadcasting packets, each MN competes for the limited radio channels. Thus, packet collision is serious. All of these aforementioned conditions are called the “Broadcast Storm Problem”. Not only it occupies the network bandwidth but it also consumes the battery of MNs. The CDS (Connected Dominating Set) scheme is a well-known solution to the “Broadcast Storm Problem”. The concept of CDS scheme is to use a few nodes to transmit the broadcasting packets. CDS provides a way to reduce flooding of the broadcasting packets while transmitting the packet to all nodes in MANET. However, finding a Minimum Connected Dominating Set (MCDS) is an NP-Complete problem. In the thesis, we want to find an approximate MCDS algorithm and use the MCDS to construct a virtual network backbone in a MANET. All nodes can transmit data effectively through the virtual backbone network. In previous research on the subject, most algorithms are only suitable for a static MANET environment, with all nodes being stationary. This is contrary to the desirable characteristics of MANET. In this dissertation, we propose an algorithm which is different from previous works to solve the Broadcast Storm Problem. The algorithm is suitable for a dynamic MANET environment.

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Ben, Khedher Dhafer. "Media handling for conferencing in MANETs." Thesis, 2007. http://spectrum.library.concordia.ca/975844/1/NR37749.pdf.

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Mobile Ad hoc NETworks (MANETs) are formed by devices set up temporarily to communicate without using a pre-existing network infrastructure. Devices in these networks are disparate in terms of resource capabilities (e.g. processing power, battery energy). Multihop Cellular Networks (MCNs) incorporate multihop mobile ad-hoc paradigms into 3G conventional single-hop cellular networks. Conferencing, an essential category of applications in MANETs and MCNs, includes popular applications such as audio/video conferencing. It is defined as an interactive multimedia service comprising online exchange of multimedia content among several users. Conferencing requires two sessions: a call signaling session and a media handling session. Call signaling is used to set up, modify, and tear down conference sessions. Media handling deals with aspects such as media transportation, media mixing, and transcoding. In this thesis, we are concerned with media handling for conferencing in MANETs and MCNs. We propose an architecture based on two overlay networks: one for mixing and one for control. The first overlay is composed of nodes acting as mixers. Each node in the network has a media connection with one mixer in the first overlay. A novel distributed mixing architecture that minimizes the number of mixers in end-to-end paths is proposed as an architectural solution for this first overlay. A sub-network of nodes, called controllers, composes the second overlay. Each controller controls a set of mixers, and collectively, they manage and control the two-overlay network. The management and control tasks are assured by a media signaling architecture based on an extended version of Megaco/H.L248. The two-overlay network is self-organizing, and thus automatically assigns users to mixers, controls mixers and controllers, and recovers the network from failures. We propose a novel self-organizing scheme that has three components: self-growing, self-shrinking and self-healing. Self-growing and self-shrinking use novel workload balancing schemes that make decisions to enable and disable mixers and controllers. The workload balancing schemes use resources efficiently by balancing the load among the nodes according to their capabilities. Self-healing detects failed nodes and recovers the network when failures of nodes with responsibilities (mixers and controllers) occur. Detection of failed nodes is based on a novel application-level failure detection architecture. A novel architecture for media handling in MCNs is proposed. We use mediator concepts to connect the media handling entities of a MANET with the media entities of a 3G cellular network. A media mediator assures signaling and media connectivity between the two networks and acts as a translator of the different media handling protocols.

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范辰銘. "Backbone-directed Dynamic Routing for MANETs." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/44151440393459500063.

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Xu, Sanlin. "Mobility Metrics for Routing in MANETs." Phd thesis, 2007. http://hdl.handle.net/1885/49272.

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A Mobile Ad hoc Network (MANET) is a collection of wireless mobile nodes forming a temporary network without the need for base stations or any other pre–existing network infrastructure. In a peer-to-peer fashion, mobile nodes can communicate with each other by using wireless multihop communication. Due to its low cost, high flexibility, fast network establishment and self-reconfiguration, ad hoc networking has received much interest during the last ten years. However, without a fixed infrastructure, frequent path changes cause significant numbers of routing packets to discover new paths, leading to increased network congestion and transmission latency over fixed networks. Many on-demand routing protocols have been developed by using various routing mobility metrics to choose the most reliable routes, while dealing with the primary obstacle caused by node mobility. ¶ In the first part, we have developed an analysis framework for mobility metrics in random mobility model. ... ¶ In the second part, we investigate the mobility metric applications on caching strategies and hierarchy routing algorithm. ...

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Bah, Slimane. "SIP servlets-based service provisioning in MANETs." Thesis, 2010. http://spectrum.library.concordia.ca/6632/1/Bah_PhD_S2010.pdf.

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Mobile Ad-hoc NETworks (MANETs) are a part of the fourth generation networks vision. They are new wireless networks having transient mobile nodes with no need for a pre-installed infrastructure. They are of utmost interest for the future networks owing to their flexibility, effortlessness of deployment and related low cost. They come in two flavours: standalone MANETs and integrated with the conventional 3G network. Providing value-added services is the core concept of several paradigms and has been extensively studied in legacy network. However, providing such services in MANETs is a challenging process. Indeed, MANETs are known for their heterogeneous devices, limited resources, dynamic topology and frequent disconnections/connections. New SIP based solutions for signalling and media handling in these networks are emerging. Furthermore, SIP is the primary protocol for 3G networks. Therefore, SIP servlets become a promising paradigm for service provisioning in MANETs. This thesis addresses the service provisioning aspects in both standalone MANETs and integrated 3G/MANETs. The SIP servlets framework is considered as the starting point while Multihop Cellular Networks (MCNs), the widely studied networks, are used as an example of integrated 3G/MANETs. Background information is provided, architectures requirements are derived and related work is reviewed. A novel business model is proposed for service provision in standalone MANETs. The business model defines the business roles and the relationship and interfaces between them. We also propose a service invocation and execution architecture implementing the business model. The solution is based on overlay network and a distribution scheme of the SIP servlets engine. The overlay network enables self-organization and self-recovery to take into account MANETs characteristics. As for the integrated 3G/MANETs we propose high level architectural alternatives for service provisioning in MCNs. We identify the most interesting alternatives from the network operator point of view and proposed a detailed and concrete architecture for the promising alternative. Overall architecture, functional entities and procedures are presented. During this work, we built prototypes as proof-of-concept and made preliminary performance measurements, used SPIN as protocol validation tool and adopted OPNET for simulation. The results show that we can provide services in MANETs as we do in conventional networks with reasonable performance.

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Jena, Sthitaprajna, and Jyotiprakash Lakra. "Application of Ant Colony optimization for MANETS." Thesis, 2009. http://ethesis.nitrkl.ac.in/1321/1/project.pdf.

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All networks tend to become more and more complicated. They can be wired, with lots of routers, or wireless, with lots of mobile nodes… The problem remains the same: in order to get the best from the network, there is a need to find the shortest path. The more complicated the network is, the more difficult it is to manage the routes and indicate which one is the best. The Nature gives us a solution to find the shortest path. The ants, in their necessity to find food and brings it back to the nest, manage not only to explore a vast area, but also to indicate to their peers the location of the food while bringing it back to the nest. Thus, they know where their nest is, and also their destination, without having a global view of the ground. Most of the time, they will find the shortest path and adapt to ground changes, hence proving their great efficiency toward this difficult task. The purpose of this project is to provide a clear understanding of the Ants-based algorithm, by giving a formal and comprehensive systematization of the subject. The simulation developed in Java will be a support of a deeper analysis of the factors of the algorithm, its potentialities and its limitations.

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Tai, Hsueh-Han, and 戴學漢. "Data Sharing Via Content-Based Router Over MANETs." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/52314113310478535632.

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碩士
輔仁大學
電機工程學系
101
The wireless networks have been widely installed in many places: such as campuses, conference halls, airports, stations, public hotspots and home areas. The primary application of networks is shifted from hardware resource sharing to content and service sharing. Such a changing also derives network applications from host-centric to content or service oriented. The requirements of file transmissions and multimedia streaming sharing grow quickly. How to provide fast and efficient content sharing over wireless networks is a primary concern. This thesis proposes a content sharing mechanism over wireless network via content-based router. The proposed content-based routers direct each user’s requirement to a stable, fast and nearest content provider so as to improve the overall system performance meanwhile upgrade the users’ service qualities. Simulation results demonstrate that the proposed scheme significantly improves the system performance.

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Dissertations / Theses on the topic 'MANETs'

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