Secure and Authenticated Message Dissemination in Vehicular ad hoc Networks and an Incentive-Based Architecture for Vehicular Cloud

Vehicular ad hoc Networks (VANETs) allow vehicles to form a self-organized network. VANETs are likely to be widely deployed in the future, given the interest shown by industry in self-driving cars and satisfying their customers various interests. Problems related to Mobile ad hoc Networks (MANETs) such as routing, security, etc.have been extensively studied. Even though VANETs are special type of MANETs, solutions proposed for MANETs cannot be directly applied to VANETs because all problems related to MANETs have been studied for small networks. Moreover, in MANETs, nodes can move randomly. On the other hand, movement of nodes in VANETs are constrained to roads and the number of nodes in VANETs is large and covers typically large area. The following are the contributions of the thesis. Secure, authenticated, privacy preserving message dissemination in VANETs: When vehicles in VANET observe phenomena such as accidents, icy road condition, etc., they need to disseminate this information to vehicles in appropriate areas so the drivers of those vehicles can take appropriate action. When such messages are disseminated, the authenticity of the vehicles disseminating such messages should be verified while at the same time the anonymity of the vehicles should be preserved. Moreover, to punish the vehicles spreading malicious messages, authorities should be able to trace such messages to their senders when necessary. For this, we present an efficient protocol for the dissemination of authenticated messages. Incentive-based architecture for vehicular cloud: Due to the advantages such as exibility and availability, interest in cloud computing has gained lot of attention in recent years. Allowing vehicles in VANETs to store the collected information in the cloud would facilitate other vehicles to retrieve this information when they need. In this thesis, we present a secure incentive-based architecture for vehicular cloud. Our architecture allows vehicles to collect and store information in the cloud; it also provides a mechanism for rewarding vehicles that contributing to the cloud. Privacy preserving message dissemination in VANETs: Sometimes, it is sufficient to ensure the anonymity of the vehicles disseminating messages in VANETs. We present a privacy preserving message dissemination protocol for VANETs

Relay assisted device-to-device communication with channel uncertainty

The gains of direct communication between user equipment in a network may not be fully realised due to the separation between the user equipment and due to the fading that the channel between these user equipment experiences. In order to fully realise the gains that direct (device-to-device) communication promises, idle user equipment can be exploited to serve as relays to enforce device-to-device communication. The availability of potential relay user equipment creates a problem: a way to select the relay user equipment. Moreover, unlike infrastructure relays, user equipment are carried around by people and these users are self-interested. Thus the problem of relay selection goes beyond choosing which device to assist in relayed communication but catering for user self-interest. Another problem in wireless communication is the unavailability of perfect channel state information. This reality creates uncertainty in the channel and so in designing selection algorithms, channel uncertainty awareness needs to be a consideration. Therefore the work in this thesis considers the design of relay user equipment selection algorithms that are not only device centric but that are relay user equipment centric. Furthermore, the designed algorithms are channel uncertainty aware. Firstly, a stable matching based relay user equipment selection algorithm is put forward for underlay device-to-device communication. A channel uncertainty aware approach is proposed to cater to imperfect channel state information at the devices. The algorithm is combined with a rate based mode selection algorithm. Next, to cater to the queue state at the relay user equipment, a cross-layer selection algorithm is proposed for a twoway decode and forward relay set up. The algorithm proposed employs deterministic uncertainty constraint in the interference channel, solving the selection algorithm in a heuristic fashion. Then a cluster head selection algorithm is proposed for device-to-device group communication constrained by channel uncertainty in the interference channel. The formulated rate maximization problem is solved for deterministic and probabilistic constraint scenarios, and the problem extended to a multiple-input single-out scenario for which robust beamforming was designed. Finally, relay utility and social distance based selection algorithms are proposed for full duplex decode and forward device-to-device communication set up. A worst-case approach is proposed for a full channel uncertainty scenario. The results from computer simulations indicate that the proposed algorithms offer spectral efficiency, fairness and energy efficiency gains. The results also showed clearly the deterioration in the performance of networks when perfect channel state information is assumed

MobiTrade: Trading Content in Disruption Tolerant Networks

International audienceThe rapid proliferation of advanced mobile devices has created a growing demand for data content. Existing approaches (e.g. relying on cellular infrastructures) cannot keep up with the large volume of content generated and requested, without the deployment of new expensive infrastructure. Exchanging content of interest opportunistically, when two nodes are in range, presents a low cost and high bandwidth alternative for popular, bulky content. Yet, efficiently collecting, storing, and sharing the content while preventing selfish users from impairing collaborative ones, poses major challenges. In this paper, we present MobiTrade, a collaborative content dissemination system on top of a delay tolerant network. It allows users to head out in the real world, express locally their interests, and wait to get notified whenever an encountered device has content(s) matching these interests. Even though interactions are done between neighboring wireless devices (locally), MobiTrade implements a trading scheme that motivates mobile devices to act as merchants and carry content across the network to satisfy each other's interests. Users continuously profile the type of content requested and the collaboration level of encountered devices. Based on this knowledge, an appropriate utility function is used to rank these requests and collect an optimal inventory of data that maximizes the expected value of stored content for future encounters. Using NS3 simulations based on synthetic and real mobility traces, we show that MobiTrade achieves up to 2 times higher query success rates compared to other content dissemination schemes. Furthermore, we show that MobiTrade successfully isolates selfish, non-collaborative devices. Finally, using a simple game theoretic framework we show that turning on our MobiTrade mechanism is an efficient Nash Equilibrium

SECURITY, PRIVACY AND APPLICATIONS IN VEHICULAR AD HOC NETWORKS

With wireless vehicular communications, Vehicular Ad Hoc Networks (VANETs) enable numerous applications to enhance traffic safety, traffic efficiency, and driving experience. However, VANETs also impose severe security and privacy challenges which need to be thoroughly investigated. In this dissertation, we enhance the security, privacy, and applications of VANETs, by 1) designing application-driven security and privacy solutions for VANETs, and 2) designing appealing VANET applications with proper security and privacy assurance. First, the security and privacy challenges of VANETs with most application significance are identified and thoroughly investigated. With both theoretical novelty and realistic considerations, these security and privacy schemes are especially appealing to VANETs. Specifically, multi-hop communications in VANETs suffer from packet dropping, packet tampering, and communication failures which have not been satisfyingly tackled in literature. Thus, a lightweight reliable and faithful data packet relaying framework (LEAPER) is proposed to ensure reliable and trustworthy multi-hop communications by enhancing the cooperation of neighboring nodes. Message verification, including both content and signature verification, generally is computation-extensive and incurs severe scalability issues to each node. The resource-aware message verification (RAMV) scheme is proposed to ensure resource-aware, secure, and application-friendly message verification in VANETs. On the other hand, to make VANETs acceptable to the privacy-sensitive users, the identity and location privacy of each node should be properly protected. To this end, a joint privacy and reputation assurance (JPRA) scheme is proposed to synergistically support privacy protection and reputation management by reconciling their inherent conflicting requirements. Besides, the privacy implications of short-time certificates are thoroughly investigated in a short-time certificates-based privacy protection (STCP2) scheme, to make privacy protection in VANETs feasible with short-time certificates. Secondly, three novel solutions, namely VANET-based ambient ad dissemination (VAAD), general-purpose automatic survey (GPAS), and VehicleView, are proposed to support the appealing value-added applications based on VANETs. These solutions all follow practical application models, and an incentive-centered architecture is proposed for each solution to balance the conflicting requirements of the involved entities. Besides, the critical security and privacy challenges of these applications are investigated and addressed with novel solutions. Thus, with proper security and privacy assurance, these solutions show great application significance and economic potentials to VANETs. Thus, by enhancing the security, privacy, and applications of VANETs, this dissertation fills the gap between the existing theoretic research and the realistic implementation of VANETs, facilitating the realistic deployment of VANETs

Journal of Telecommunications and Information Technology

kwartalni

Multi-Stakeholder Consensus Decision-Making Framework Based on Trust and Risk

Indiana University-Purdue University Indianapolis (IUPUI)This thesis combines human and machine intelligence for consensus decision-making, and it contains four interrelated research areas. Before presenting the four research areas, this thesis presents a literature review on decision-making using two criteria: trust and risk. The analysis involves studying the individual and the multi-stakeholder decision-making. Also, it explores the relationship between trust and risk to provide insight on how to apply them when making any decision. This thesis presents a grouping procedure of the existing trust-based multi-stakeholder decision-making schemes by considering the group decision-making process and models. In the first research area, this thesis presents the foundation of building multi-stakeholder consensus decision-making (MSCDM). This thesis describes trust-based multi-stakeholder decision-making for water allocation to help the participants select a solution that comes from the best model. Several criteria are involved when deciding on a solution such as trust, damage, and benefit. This thesis considers Jain's fairness index as an indicator of reaching balance or equality for the stakeholder's needs. The preferred scenario is when having a high trust, low damages and high benefits. The worst scenario involves having low trust, high damage, and low benefit. The model is dynamic by adapting to the changes over time. The decision to select is the solution that is fair for almost everyone. In the second research area, this thesis presents a MSCDM, which is a generic framework that coordinates the decision-making rounds among stakeholders based on their influence toward each other, as represented by the trust relationship among them. This thesis describes the MSCDM framework that helps to find a decision the stakeholders can agree upon. Reaching a consensus decision might require several rounds where stakeholders negotiate by rating each other. This thesis presents the results of implementing MSCDM and evaluates the effect of trust on the consensus achievement and the reduction in the number of rounds needed to reach the final decision. This thesis presents Rating Convergence in the implemented MSCDM framework, and such convergence is a result of changes in the stakeholders' rating behavior in each round. This thesis evaluates the effect of trust on the rating changes by measuring the distance of the choices made by the stakeholders. Trust is useful in decreasing the distances. In the third research area, this thesis presents Rating Convergence in the implemented MSCDM framework, and such convergence is a result of changes in stakeholders' rating behavior in each round. This thesis evaluates the effect of trust on the rating changes by measuring the perturbation in the rating matrix. Trust is useful in increasing the rating matrix perturbation. Such perturbation helps to decrease the number of rounds. Therefore, trust helps to increase the speed of agreeing upon the same decision through the influence. In the fourth research area, this thesis presents Rating Aggregation operators in the implemented MSCDM framework. This thesis addresses the need for aggregating the stakeholders' ratings while they negotiate on the round of decisions to compute the consensus achievement. This thesis presents four aggregation operators: weighted sum (WS), weighted product (WP), weighted product similarity measure (WPSM), and weighted exponent similarity measure (WESM). This thesis studies the performance of those aggregation operators in terms of consensus achievement and the number of rounds needed. The consensus threshold controls the performance of these operators. The contribution of this thesis lays the foundation for developing a framework for MSCDM that facilitates reaching the consensus decision by accounting for the stakeholders' influences toward one another. Trust represents the influence

Knowledge Management in Rural Uzbekistan : Peasant, Project and Post-Socialist perspectives in Khorezm

Agricultural knowledge is important in rural Uzbekistan. Presented in this thesis is sociological data from field research in the Khorezm region of Uzbekistan, illustrating the ways in which knowledge operates in a certain context of power and culture. The way in which this agricultural knowledge is created, shared, stored and used is discussed in this thesis on the basis of three ‘systems’ of knowledge. These knowledge systems; peasant, project and post-Socialist are used to understand how agricultural knowledge is used differently. The peasant system constitutes the local knowledge of the rural community in the Khorezm province of Uzbekistan. Within this province a development research project, through which this research was conducted, also operates and the particular approach to knowledge creation and sharing is discussed here. Finally, both these systems operate within a knowledge ‘governance’ structure which establishes the ‘rules of the game’ for the region. Yet what we find in all three of these systems is that three phenomena of knowledge exist, in varying ways, in agriculture in Khorezm. These three phenomena are: (i) Knowledge dynamics: how knowledge is made, lost and destroyed, (ii) Power and Knowledge: the interplay of knowledge and power, (iii) Knowledge and Culture: why culture matters in knowledge management. Knowledge loss, especially in the post-1991 period is crucial to understanding the economic and ecological challenges in rural Khorezm and the process of knowledge loss (and creation) is prevalent in my research. Specific to the local knowledge system, evidence is presented that whilst specialisation is inherent in any knowledge system; this characteristic of the knowledge system is embedded in the patriarchal and hierarchal nature of Uzbek culture, and the position of power that this entails. Similarly, I examine the modes of knowledge reproduction within Khorezm and find these to be overwhelmingly family based, even in cases where formal education is necessary, although there are examples of external forms of knowledge being accessed and then reproduced within the knowledge system. I find that in all three systems there is a complex interplay of knowledge and power, with a mutually reinforcing of each occurring in social interactions, within and between the knowledge systems. Finally the phenomena of knowledge loss and knowledge/power relations are grounded in a specific cultural context and it is argued that the peculiarities of Khorezm, including the Soviet history and a specific understanding of authority (joshuli), means that knowledge is shaped and informed by the cultural context from which it is drawn. These findings are then discussed in terms of the theoretical implications of this research which argue for a wider appreciation of knowledge loss and deeper analysis of power/knowledge interactions. Finally, practical development advice is given on how foreign projects can better develop local knowledge in Uzbekistan, by seeing agricultural knowledge as it operates in the cultural context of Khorezm and by accessing local knowledge

Applications

Volume 3 describes how resource-aware machine learning methods and techniques are used to successfully solve real-world problems. The book provides numerous specific application examples: in health and medicine for risk modelling, diagnosis, and treatment selection for diseases in electronics, steel production and milling for quality control during manufacturing processes in traffic, logistics for smart cities and for mobile communications

Técnicas de computación social e información contextual para el desarrollo de actividades de aprendizaje colaborativo

[EN]Educational innovation is a field in which its processes has been greatly enriched by the use of Information and Communication Technologies (ICT). Thanks to technological advances, the use of learning models where information comes from many different sources is now usual. Likewise, student-student, student-device and device-device collaborations provides added value to the learning processes thanks to the fact that, through it, aspects such as communication, achievement of common goals or sharing resources. Within the educational innovation, we find as a great challenge the development of tools that facilitate the creation of innovative collaborative learning processes that improve the achievement of the objectives sought, with respect to individualized processes, and the fidelity of the students to the process through the use of contextual information. Moreover, the development of these solutions, that facilitate the work of teachers, developers and technicians encouraging the production of educational processes more attractive to students, presents itself as an ambitious challenge in which the perspectives of Ambient Intelligence and Social Computing play a key role. The doctoral dissertation presented here describes and evaluates CAFCLA, a framework specially conceived for the design, development and implementation of collaborative learning activities that make use of contextual information and that is based on the paradigms of Ambient Intelligence and Social Computing. CAFCLA is a flexible framework that covers the entire process of developing collaborative learning activities and hides all the difficulties involved in the use and integration of multiple technologies to its users. In order to evaluate the validity of the proposal, CAFCLA has supported the implementation of three concrete and different use cases. These experimental use cases have shown that, among other benefits, the use of Social Computing customizes the learning process, encourages collaboration, improves relationships, increases commitment, promotes behaviour change in users and enables learning to be maintained over time. In addition, in order to demonstrate the flexibility of the framework, these use cases have been developed in different scenarios (such as a museum, a public building or at home), different types of learning have been proposed (serious games, recommendations system orWebQuest) and different learning objectives have been chosen (academic, social and energy-efficient).[ES]La innovación educativa es un campo que ha sido enormemente enriquecido por el uso de las Tecnologías de la Información y las Comunicaciones (TIC) en sus procesos. Gracias a los avances tecnológicos, actualmente es habitual el uso de modelos de aprendizaje donde la información proviene de numerosas y diferentes fuentes. De igual forma, la colaboración estudiante-estudiante, estudiante-dispositivo y dispositivo-dispositivo, proporciona un valor añadido a los procesos de aprendizaje gracias a que, a través de ella, se fomentan aspectos como la comunicación, la consecución de una meta común, o la compartición de recursos. Dentro de la innovación educativa encontramos como un gran desafío el desarrollo de herramientas que faciliten la creación de procesos de aprendizaje colaborativo innovadores que mejoren los resultados obtenidos, respecto a los procesos individualizados, y la fidelidad de los estudiantes al proceso mediante el uso de información contextual.Más aún, el desarrollo de soluciones que faciliten el trabajo a profesores, desarrolladores y técnicos, fomentando la producción de procesos educativos más atractivos para los estudiantes, se presenta como un ambicioso reto en el que las perspectivas de la Inteligencia Ambiental y la Computación Social juegan un papel fundamental. La tesis doctoral aquí presentada describe y evalúa CAFCLA, un framework especialmente concebido para el diseño, desarrollo e implementación de actividades de aprendizaje colaborativo que hagan uso de información contextual basándose en los paradigmas de la Inteligencia Ambiental y la Computación Social. CAFCLA es un framework flexible que abarca todo el proceso de desarrollo de actividades de aprendizaje colaborativo y oculta todas las dificultades que implican el uso e integración de múltiples tecnologías a sus usuarios. Para evaluar la validez de la propuesta realizada, CAFCLA ha soportado la implementación de tres casos de uso concretos y diferentes entre sí. Estos casos de uso experimentales han demostrado que, entre otros beneficios, el uso de la Computación Social personaliza el proceso de aprendizaje, fomenta la colaboración, mejora las relaciones, aumenta el compromiso, favorecen el cambio de comportamiento en los usuarios y mantiene su implicación en el proceso a lo largo del tiempo. Además, con el objetivo de demostrar la flexibilidad del framework, estos casos de uso se han desarrollado en diferentes escenarios (como un museo, un edificio público o el hogar), se han propuesto diferente tipos de aprendizaje (juegos serios, sistema de recomendaciones o WebQuest) y se han elegido diferentes objetivos de aprendizaje (académicos, sociales y de eficiencia energética)