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Vehicular Ad-Hoc Networks (VANETs) are a fast growing technology that many governments and automobile manufacturers are investing in to provide not only safer and more secure roads, but also informational and entertainment-based applications for drivers. The applications developed for VANETs can be classified into multiple categories (safety, informational, entertainment). Most VANET applications, regardless of their category, depend on having certain vehicular data(vehicular speed, X position and Y position) available. Although these applications appear to use the same vehicular data, the characteristics of this data (i.e., amount, accuracy, and update rate) will vary based on the application category. For example, safety applications need an accurate version of the vehicular datawith high frequency, but over short distances. Informational applications relax the data frequency constraint as they need the vehicular data to be reasonably accurate with less frequency, but over longer distances. If each of these applications shares the vehicular data with only its peers using its own mechanism, this behavior will not only introduce redundant functionalities (sending, receiving, processing, etc.) for handling the same data, but also wastefully consume the bandwidth by broadcasting the same data multiple times. Despite the differences in the data characteristics needed by each application, this data can be still shared. Vehicular networks introduce the potential for many co-existing applications. If we do not address the problem of data redundancy early, it may hinder the deployment and usefulness of many of these applications. Therefore, we developed a framework, cluster-based accurate syntactic compression of aggregated data in VANETs (CASCADE), for efficiently aggregating and disseminating commonly-used vehicular data. CASCADE is architccted as a layer that provides applications with a customized version of the vehicular data, based on parameters that each application registers with CASCADE. Additionally, the framework performs the common data handling functionalities (sending, receiving, aggregating, etc.) needed by the applications. This dissertation makes the following contributions: (1) a lossless data compression technique based on differential coding that is tailored for the characteristics of vehicular data; (2) a syntactic data aggregation mechanism that can represent the vehicular data in a 1.5 km area in one IEEE 802.11 frame; (3) a light-weight position verification technique that quickly detects false data with very low false positives; (4) a probabilistic data dissemination technique that alleviates the spatial broadcast storm problem and effectively uses the bandwidth to disseminate data to distant areas in a short amount of time inaddition to having less redundancy and more coverage than other techniques. (5) a mechanism for recovering from the communication discontinuity problem inshort time based on the traffic density in the opposite direction; (6) an investigation of the possible data structures for representing the vehicular data in a searchable format; (7) a parametric mechanism for matching the vehicular data and providing a customized version of the data that satisfies certain characteristics based on the parameter value. CASCADE through its four major components, local view, extended view, data security and data dissemination, provides an efficient solution for the problem of scalability for VANET applications.

The present paper focused on ad hoc networks with an emphasis on their dynamic nature. After an introduction to ad hoc networks, there are the AODV (Ad hoc On-demand Distance Vector) routing protocol with the node malicious behaviour and consequent damages to ad hoc networks. Then, trust is described as one of the solutions for identifying secure routes when there are malicious nodes in the network. Accordingly, the paper focuses on the proposed solutions that are based on the parameter trust and the prevention of the impact of malicious networks and vulnerable connections to identify a secure route. Then, an equation is presented to calculate trust using packet forwarding rate to select a secure route for sending data packets. The proposed model was implemented on OMNET++ to evaluate the network performance. The feature of the proposed method is better performance than of the methods TVAODV and AODV. Using the proposed method, packet delivery rate increases more significantly when malicious nodes increases than that of the basic method AODV and TVAODV. There is thus a lower packet dropping rate.

The Mobile Ad Hoc Network (MANET) has emerged as the next frontier for wireless communications networking in both the military and commercial arena. Handbook of Mobile Ad Hoc Networks for Mobility Models introduces 40 different major mobility models along with numerous associate mobility models to be used in a variety of MANET networking environments in the ground, air, space, and/or under water mobile vehicles and/or handheld devices. These vehicles include cars, armors, ships, under-sea vehicles, manned and unmanned airborne vehicles, spacecrafts and more. This handbook also describes how each mobility pattern affects the MANET performance from physical to application layer; such as throughput capacity, delay, jitter, packet loss and packet delivery ratio, longevity of route, route overhead, reliability, and survivability. Case studies, examples, and exercises are provided throughout the book. About this handbook: Presents a cutting-edge treatment of the fundamental role mobility models play in analyzing and designing MANET Describes 40 different major mobility models along with numerous associate mobility models and their impact on MANET performances comprehensively Fills a void in commercial, military, and the research arena for multihop mobile ad hoc networking Provides case studies, examples, and exercises throughout the book "There has been a wide variety of research in Mobile Ad-hoc Network (MANET) over past many years and there are many models. As the application of wireless technology has grown in recent years in the commercial and military applications, the practitioners and engineers are finding it difficult to make informed choices on how best to apply MANET. This book will provide focus and foundation for these decision makers," comments Dr. Anupam Shah, Chief Engineer of Enterprise & Mission Solutions Business Unit, Science Applications International Corporation (SAIC). Handbook of Mobile Ad Hoc Networks for Mobility Models is for advanced-level students and researchers concentrating on electrical engineering and computer science within wireless technology. Industry professionals working in the areas of mobile ad hoc networks, communications engineering, military establishments engaged in communications engineering, equipment manufacturers who are designing radios, mobile wireless routers, wireless local area networks, and mobile ad hoc network equipment will find this book useful as well

This book presents "vehicular ad-hoc networks" (VANETs) from the their onset, gradually going into technical details, providing a clear understanding of both theoretical foundations and more practical investigation. The editors gathered top-ranking authors to provide comprehensiveness and timely content; the invited authors were carefully selected from a list of who s who in the respective field of interest: there are as many from Academia as from Standardization and Industry sectors from around the world. The covered topics are organized around five Parts starting from an historical overview of vehicular communications and standardization/harmonization activities (Part I), then progressing to the theoretical foundations of VANETs and a description of the day-one standard-compliant solutions (Part II), hence going into details of vehicular networking and security (Part III) and to the tools to study VANETs, from mobility and channel models, to network simulators and field trial methodologies (Part IV), and finally looking into the future of VANETs by investigating alternative, complementary communication technologies, innovative networking paradigms and visionary applications (Part V). The way the content is organized, with a differentiated level of technical details, makes the book a valuable reference for a large pool of target readers ranging from undergraduate, graduate and PhD students, to wireless scientists and engineers, to service providers and stakeholders in the automotive, ITS, ICT sectors."

In the recent time, there will be an increasing need to provide application platforms such as internet deployment for areas without infrastructure, wireless video streaming between moving objects, data exchange between office equipment etc. These applications can be solved with the help of wireless ad hoc networks that can be realized e.g., with Wi-Fi protocols. The question arises, what theoretical throughput different wireless standards can achieve, and how much the throughput will decrease when data has to be transferred over several hops. This is a technology that enables un tethered wireless networking environments where there is no wired or cellular infrastructure. Wireless Ad hoc Networks since then is a fast developing research area with a vast spectrum of applications. Wireless sensor network systems enable the reliable monitoring of a variety of environments for both civil and military applications

Ideally a hash tree is a perfect binary tree with leaves equal to power of two. Each leaf node in this type of tree can represent a mobile node in an ad hoc network. Each leaf in the tree contains hash value of mobile node's identification (ID) and public key (PK). Such a tree can be used for authenticating PK in ad hoc networks. Most of the previous works based on hash tree assumed perfect hash tree structures, which can be used efficiently only in networks with a specific number of mobile nodes. Practically the number of mobile nodes may not be always equal to a power of two and the conventional algorithms may result in an inefficient tree structure. In this paper the issue of generating a hash tree is addressed by proposing an algorithm to generate an optimally-balanced structure for a complete hash tree. It is demonstrated through both the mathematical analysis and simulation that such a tree is optimally-balanced and can efficiently be used for public key authentication in ad hoc networks.

Realistic simulation scenarios are critical for correctly assessing the performance of mobile ad hoc networks. This paper presents a tool to generate realistic mobility traces for MANET simulations. A new mobility module called AMADEOS was developed as an extension for the CANUMobisim framework. AMADEOS makes it easy and fast to automatically generate realistic mobility. It allows editing spatial environments with polygonal obstacles to be used within simulations. It also allows visualizing an animation of the generated mobility traces. To model mobility for simulation environments, a new mobility model was created that takes into account obstacles. A new propagation model based on ray tracing was also implemented as part of AMADEOS. AMADEOS was used to re-evaluate the performance of the AODV routing protocol in some realistic scenarios.

A mobile ad hoc network (MANET) is a wireless network that uses multi-hop peer-to-peer routing instead of static network infrastructure to provide network connectivity. MANETs have applications in rapidly deployed and dynamic military and civilian systems. The network topology in a MANET usually changes with time. Therefore, there are new challenges for routing protocols in MANETs since traditional routing protocols may not be suitable for MANETs. For example, some assumptions used by these protocols are not valid in MANETs or some protocols cannot efficiently handle topology changes. Researchers are designing new MANET routing protocols and comparing and improving existing MANET routing protocols before any routing protocols are standardized using simulations. However, the simulation results from different research groups are not consistent with each other. This is because of a lack of consistency in MANET routing protocol models and application environments, including networking and user traffic profiles. Therefore, the simulation scenarios are not equitable for all protocols and conclusions cannot be generalized. Furthermore, it is difficult for one to choose a proper routing protocol for a given MANET application. According to the aforementioned issues, my Ph.D. research focuses on MANET routing protocols. Specifically, my contributions include the characterization of differ- ent routing protocols using a novel systematic relay node set (RNS) framework, design of a new routing protocol for MANETs, a study of node mobility, including a quantitative study of link lifetime in a MANET and an adaptive interval scheme based on a novel neighbor stability criterion, improvements of a widely-used network simulator and corresponding protocol implementations, design and development of a novel emulation test bed, evaluation of MANET routing protocols through simulations, verification of our routing protocol using emulation, and development of guidelines for one to choose proper MANET routing protocols for particular MANET applications. Our study shows that reactive protocols do not always have low control overhead, as people tend to think. The control overhead for reactive protocols is more sensitive to the traffic load, in terms of the number of traffic flows, and mobility, in terms of link connectivity change rates, than other protocols. Therefore, reactive protocols may only be suitable for MANETs with small number of traffic loads and small link connectivity change rates. We also demonstrated that it is feasible to maintain full network topology in a MANET with low control overhead. This dissertation summarizes all the aforementioned methodologies and corresponding applications we developed concerning MANET routing protocols. ; Ph. D.

17 USC 105 interim-entered record; under temporary embargo. ; Cyber attacks are amongst the most serious threats facing people and organizations. In the face of the increasing complexity and effectiveness of these attacks, creative approaches to defense are required. Groups of insects survive due to their use of collaborative approaches with the unique ability to detect anomalies using primarily local data and very limited computational resources (i.e., limited brain power). These attributes are even more crucial for wireless ad hoc networks where the number of nodes and connections between those nodes are ephemeral. We propose a trust framework inspired by the detection mechanisms exhibited by bee swarms in which a wireless node can only observe and leverage the actions of their neighbors rather than the global knowledge of the network to make a decision. This leveraging of local knowledge is an important aspect of trust in wireless networks in which global state information is difficult to encapsulate. We also utilize models from binary voting to present a straightforward mathematical model for our bee-inspired trust framework in wireless ad hoc networks. ; U.S. Government affiliation is unstated in article text.

Modern communication systems are characterized by an increasing need for self-configuring networks. In fact, in many practical cases, the presence of centralizing devices such as a base station is neither realistic nor practical. This is the case, for instance, in military or emergency situation, or when the increasingly dense deployment of access points makes a man-made planning unfeasible. As a consequence, problems like designing behavioral rules for devices (or groups of devices) on how to select their own transmit parameters naturally arise. In particular, self-configuring algorithms must be able to respond to the necessity of detecting, avoiding or reducing interference, thus maintaining a sufficient quality of the communications when no centralization is available, and with minimum information exchange and cooperation. Moreover, these algorithms must be able to cope with the variations of the transmission conditions due to fading, shadowing, mobility and to the change in other devices behavioral patterns eventually creating extra interference.The goal of this thesis is to study the joint problem of channel selection and power control in the context of multiple-channel clustered ad-hoc networks, i.e., decentralized networks in which radio devices are arranged into groups known as clusters, and to propose a viable decentralized self-configuring algorithm for such a network.The network is studied and analyzed through game theory, and the relative equilibria are identified. The first purpose is to use these equilibria in order to quantify the performance of different algorithms that originate from the theory of learning in games. An algorithm based on the trial and error paradigm is then selected as a candidate solution. A particular utility function is designed in order for the equilibria to coincide with the solutions of an optimization problem, thus maximizing the quality of the communications while minimizing the resources needed. These results are presented in the most general form and therefore, they can also be seen as a framework for designing both games and learning algorithms with which decentralized networks can operate atglobal optimal points using only their available local knowledge. The pertinence of the game design and the learning algorithm are highlighted using specific scenarios in decentralized clustered ad hoc networks. Numerical results confirm the relevance of using appropriate utility functions and trial and error learning for enhancing the performance of decentralized networks. ; Les systèmes de communication modernes sont caractérisés par leur besoin croissant en mécanismes d'auto-configuration. En effet, dans de nombreux cas pratiques, la présence de dispositifs de centralisation tel qu'une station de base n'est ni réaliste ni pratique. Ceci est le cas, par exemple, des situations militaires ou aussi celles d'urgence, ou lorsque le déploiement de plus en plus dense de points d'accès rend la planification humaine irréalisable. Par conséquent, des problèmes tel que la conception de règles de comportement pour les appareils (ou groupes d'appareils) sur la fa¸ con de choisir leurs propres paramètres de transmission, se présentent naturellement. En particulier, les algorithmes d'auto-configuration doivent être en mesure de répondre à la nécessité de détecter, d'éviter ou de réduire les interférences, maintenant ainsi une qualité suffisante de communications quand une centralisation est indisponible, et ceci avec un minimum d'échange d'informations et de coopération. En outre, ces algorithmes doivent être en mesure de faire face aux variations naturelles des conditions d'émission, en raison de l'atténuation, des effets de masque, de la mobilité et de la variation des comportements des autres dispositifs qui peuvent éventuellement créer des interférences supplémentaires. L'objectif de cette thèse est d'étudier le problème conjoint de sélection de canal et de contrôle de puissance dans le contexte de réseaux ad hoc clustérisés à canaux multiples, c'est à dire, des réseaux décentralisés dans lesquels les appareils radio sont disposés en groupes appelés clusters, et de proposer un algorithme d'auto-configuration décentralisé viable pour un tel réseau.Le réseau est étudié et analysé par l'intermédiaire de la théorie des jeux, et les équilibres relatifs sont identifiés. Le premier objectif consiste à utiliser ces équilibres afin de quantifier les performances des différents algorithmes qui proviennent de la théorie de l'apprentissage dans les jeux. Un algorithme basé sur le paradigme "trial and error" est alors sélectionné en tant que solution candidat. Une fonction d'utilité particulière est conçue afin que l'équilibre puisse coïncider avec les solutions d' un problème d'optimisation, maximisant ainsi la qualité des communications, tout en minimisant les ressources nécessaires. Ces résultats sont présentés sous la forme la plus générale et, par conséquent, ils peuvent ˆ être aussi considérés comme un cadre théorique général pour la conception des jeux, ainsi que des algorithmes d'apprentissage avec lesquels les réseaux décentralisés peuvent fonctionner à des points optimaux globaux, et ceci à l'aide uniquement de leurs connaissances locales disponibles. La pertinence de la conception du jeu ainsi que de l'algorithme d'apprentissage est mis en évidence au moyen de scénarios spécifiques dans des réseaux ad hoc clustérisés et décentralisés. Les résultats numériques confirment la pertinence de l'utilisation des fonctions utilitaires appropriées ainsi que de l'apprentissage "trial and error" dans l'amélioration de la performance des réseaux décentralisés.

Modern communication systems are characterized by an increasing need for self-configuring networks. In fact, in many practical cases, the presence of centralizing devices such as a base station is neither realistic nor practical. This is the case, for instance, in military or emergency situation, or when the increasingly dense deployment of access points makes a man-made planning unfeasible. As a consequence, problems like designing behavioral rules for devices (or groups of devices) on how to select their own transmit parameters naturally arise. In particular, self-configuring algorithms must be able to respond to the necessity of detecting, avoiding or reducing interference, thus maintaining a sufficient quality of the communications when no centralization is available, and with minimum information exchange and cooperation. Moreover, these algorithms must be able to cope with the variations of the transmission conditions due to fading, shadowing, mobility and to the change in other devices behavioral patterns eventually creating extra interference.The goal of this thesis is to study the joint problem of channel selection and power control in the context of multiple-channel clustered ad-hoc networks, i.e., decentralized networks in which radio devices are arranged into groups known as clusters, and to propose a viable decentralized self-configuring algorithm for such a network.The network is studied and analyzed through game theory, and the relative equilibria are identified. The first purpose is to use these equilibria in order to quantify the performance of different algorithms that originate from the theory of learning in games. An algorithm based on the trial and error paradigm is then selected as a candidate solution. A particular utility function is designed in order for the equilibria to coincide with the solutions of an optimization problem, thus maximizing the quality of the communications while minimizing the resources needed. These results are presented in the most general form and therefore, they ...

Les xarxes mòbils ad-hoc, també conegues com a MANETs, han estat des de fa ja molt temps objectiu d'estudi per part de la comunitat científica. No obstant això, la seva importància dins el món de la indústria és encara molt baix. Aquests tipus de xarxes, formades per dispositius mòbils tals com smartphones o portàtils, poden ser usades per exemple en entorns mòbils com els campus universitaris, els centres de conferència, o en les indústries militars, de seguretat ciutadana, etc. Per poder establir comunicacions fiables entre els diferents dispositius d'una MANET fa falta un stack de comunicacions. Des de sempre, la comunitat científica ha basat els seus esforços en optimitzar l'stack de comunicacions TCP/IP, l'stack per excel·lència en la majoria de les xarxes actuals. Enlloc de dissenyar un nou stack de comunicacions, els científics han intentat adaptar i millorar les solucions ja existents provinents del món de les xarxes cablejades. Nosaltres, en canvi, creiem que un nou stack de comunicacions específicament dissenyat per a les MANETs és indispensable si el que volem és aconseguir comunicacions fiables en aquest tipus de xarxes, les quals tenen propietats molt diferents a les de les xarxes cablejades. En aquesta tesi presentem el que avui en dia encara no existeix: un nou stack de comunicacions específicament dissenyat per MANETs. Aquest stack és un exemple de com molts dels mecanismes usats en el món de les xarxes cablejades han de ser redissenyats des de la seva base si del que es tracta és de dissenyar protocols per a xarxes mòbils ad-hoc. En definitiva, nosaltres creiem que els resultats presentats en aquesta tesi demostren el potencial d'aquest nou stack de comunicacions per a les MANETs. ; Mobile ad-hoc networks have received considerable attention in the wireless communications research community. Nevertheless, its importance in industry is still low. Self-organized MANETs of smartphones or laptops can be used, for example, in military, public safety and disaster relief, conference, or campus environments. In order to enable communications between nodes inside a MANET, a communications stack is needed in each node of the network. Research in this area was always focused on optimizing the TCP/IP stack, the stack par excellence in the majority of our current networks. Instead of designing a complete new communications stack, researchers focused their work mainly on improving already existing solutions coming from the wired networks. However, we think that a complete and new communications stack specifically designed for MANETs is needed if we want to achieve robust communications in this type of networks, which have properties very different from what wired networks have. In this thesis we present what nowadays is still missing: a novel communications stack specifically designed for mobile ad-hoc networks. The MStack is an example of how some of the basic assumptions and mechanisms used in wired or wireless infrastructure networks must be fundamentally modified when dealing with MANETs. All in all, we believe that the results presented in this thesis provide interesting insights into the potential of the MStack in MANETs. ; Postprint (published version)