Blockchain Based Decentralized Applications & Trust Management for VANETs

Decentralized vehicular Ad-hoc Networks (VANETs), a promising technology to improve the Intelligent Transportation System (ITSs), face severe lagging in actual deployment and its extensive usage due to major unresolved issues such as security, data reliability, user privacy, and safe routing protocols. To overcome these issues, there is an urge to identify a platform that best suits VANET's easy deployment and usage in a decentralized fashion. In this regard, blockchain has received much attention as an emerging technology to provide better security on data sharing among many participants without an intermediary. This thesis aims to investigate blockchain technology's capability to secure vehicular data and vehicular node trust scores over a tamper-proof decentralized ledger that guarantees security, immutability, and accountability in Peer-to-Peer (P2P) networks such as VANET.Firstly, we explore how to leverage blockchain technology to design a specific application in the domain of decentralized VANETs, such as ride-sharing. We analyze the decentralized architecture for this application using smart contracts, and through experiments, we evaluate the costs associated with it. This framework serves as a basis for our further study to solve more challenging research problems in the consensus algorithm. The choice of a consensus algorithm directly affects the performance of a blockchain-based system in terms of transaction confirmation delays. In a VANET based on blockchain, the Proof of Work (PoW) and Proof of Stake (PoS) consensus might not be the best selection due to resource constraints and unfairness, respectively. In an attempt to improve consensus in a VANET application based on blockchain, we present the design of a novel consensus mechanism named Proof Of Driving for our previously presented ride-sharing application. We demonstrated that POD clubbed with a real-time service standard score protocol efficiently optimizes the number of miner nodes. The extensive experimental and security analyses presented on proposed consensus and service standard protocols demonstrate the effectiveness, security, and feasibility of miner node selection. However, VANET is not secure as vehicular communication is critically vulnerable to several kinds of active and passive routing protocol attacks. The most severe attack in routing is the Black Hole attack, which deteriorates the network's performance by dropping or misusing the intercepted data packets without forwarding them to the correct destination. This greatly hinders the application availability. Hence in the final chapter of this thesis, we experiment by incorporating trust models in VANET routing protocols to achieve a more efficient packet forwarding process. The results showed an improved packet delivery ratio and throughput of the entire network. The trust model should be able to resist various attacks and preserve the privacy of vehicles simultaneously. Hence we presented how to leverage consortium blockchain to secure vehicles' trust scores and distribute node trust in a decentralized network more efficiently. We evaluated the trust score aggregation process by the authorized RSUs, the time consumed for consensus, and updated trust score distribution. The results showed that the blockchain-based trust management provides an effective trust model for VANETs with transparency, conditional anonymity, efficiency, and robustness while efficiently eliminates the black hole nodes

Lever: Breaking the Shackles of Scalable On-chain Validation

Blockchain brings dawn to decentralized applications which coordinate correct computations without a prior trust. However, existing scalable on-chain frameworks are incompetent in dealing with intensive validation. On the one hand, duplicated execution pattern leads to limited throughput and unacceptable expenses. On the other hand, there lack fair and secure incentive mechanisms allocating rewards according to the actual workload of validators, thus deriving bad dilemmas among rational participants and inducing effective attacks from shrewd adversaries. While most solutions rely on off-chain patterns to sidestep the shackles, it further introduces unexpected issues in applicability, fairness and brittle dependency on interactive cooperation. The intrinsic bottleneck of backbone has never been drastically broken. This work presents Lever, the first scalable on-chain framework which supports intensive validation, meanwhile achieves validity, incentive compatibility and cost-efficiency tolerance of f<n/4 Byzantine participants. Lever firstly integrates the evaluation of complexity into the correctness of transaction, thoroughly decoupling intensive validation from regular Byzantine consensus. Significant scalability is then achieved by launching few rounds of novel validation-challenge game between potential adversaries and rational stakeholders; compelling incentive mechanism effectively transfers deposits of adversary to specialized rewards for honest validators, therefore allows the user to lever sufficient endorsement for verification with minimum cost. Combined with game-theoretic insights, a backstop protocol is designed to ensure finality and validity of the framework, breaking through the famous Verifier’s Dilemma. Finally, we streamline Lever under the efficient architecture of sharding, which jointly shows robust to conceivable attacks on validation and performs outstanding ability to purify Byzantine participants. Experimental results show that Lever vastly improves the throughput and reduces expenses of intensive validation with slight compromise in latency

Wide-Area Situation Awareness based on a Secure Interconnection between Cyber-Physical Control Systems

Posteriormente, examinamos e identificamos los requisitos especiales que limitan el diseño y la operación de una arquitectura de interoperabilidad segura para los SSC (particularmente los SCCF) del smart grid. Nos enfocamos en modelar requisitos no funcionales que dan forma a esta infraestructura, siguiendo la metodología NFR para extraer requisitos esenciales, técnicas para la satisfacción de los requisitos y métricas para nuestro modelo arquitectural. Estudiamos los servicios necesarios para la interoperabilidad segura de los SSC del SG revisando en profundidad los mecanismos de seguridad, desde los servicios básicos hasta los procedimientos avanzados capaces de hacer frente a las amenazas sofisticadas contra los sistemas de control, como son los sistemas de detección, protección y respuesta ante intrusiones. Nuestro análisis se divide en diferentes áreas: prevención, consciencia y reacción, y restauración; las cuales general un modelo de seguridad robusto para la protección de los sistemas críticos. Proporcionamos el diseño para un modelo arquitectural para la interoperabilidad segura y la interconexión de los SCCF del smart grid. Este escenario contempla la interconectividad de una federación de proveedores de energía del SG, que interactúan a través de la plataforma de interoperabilidad segura para gestionar y controlar sus infraestructuras de forma cooperativa. La plataforma tiene en cuenta las características inherentes y los nuevos servicios y tecnologías que acompañan al movimiento de la Industria 4.0. Por último, presentamos una prueba de concepto de nuestro modelo arquitectural, el cual ayuda a validar el diseño propuesto a través de experimentaciones. Creamos un conjunto de casos de validación que prueban algunas de las funcionalidades principales ofrecidas por la arquitectura diseñada para la interoperabilidad segura, proporcionando información sobre su rendimiento y capacidades.Las infraestructuras críticas (IICC) modernas son vastos sistemas altamente complejos, que precisan del uso de las tecnologías de la información para gestionar, controlar y monitorizar el funcionamiento de estas infraestructuras. Debido a sus funciones esenciales, la protección y seguridad de las infraestructuras críticas y, por tanto, de sus sistemas de control, se ha convertido en una tarea prioritaria para las diversas instituciones gubernamentales y académicas a nivel mundial. La interoperabilidad de las IICC, en especial de sus sistemas de control (SSC), se convierte en una característica clave para que estos sistemas sean capaces de coordinarse y realizar tareas de control y seguridad de forma cooperativa. El objetivo de esta tesis se centra, por tanto, en proporcionar herramientas para la interoperabilidad segura de los diferentes SSC, especialmente los sistemas de control ciber-físicos (SCCF), de forma que se potencie la intercomunicación y coordinación entre ellos para crear un entorno en el que las diversas infraestructuras puedan realizar tareas de control y seguridad cooperativas, creando una plataforma de interoperabilidad segura capaz de dar servicio a diversas IICC, en un entorno de consciencia situacional (del inglés situational awareness) de alto espectro o área (wide-area). Para ello, en primer lugar, revisamos las amenazas de carácter más sofisticado que amenazan la operación de los sistemas críticos, particularmente enfocándonos en los ciberataques camuflados (del inglés stealth) que amenazan los sistemas de control de infraestructuras críticas como el smart grid. Enfocamos nuestra investigación al análisis y comprensión de este nuevo tipo de ataques que aparece contra los sistemas críticos, y a las posibles contramedidas y herramientas para mitigar los efectos de estos ataques

Ecology-based planning. Italian and French experimentations

This paper examines some French and Italian experimentations of green infrastructures’ (GI) construction in relation to their techniques and methodologies. The construction of a multifunctional green infrastructure can lead to the generation of a number of relevant bene fi ts able to face the increasing challenges of climate change and resilience (for example, social, ecological and environmental through the recognition of the concept of ecosystem services) and could ease the achievement of a performance-based approach. This approach, differently from the traditional prescriptive one, helps to attain a better and more fl exible land-use integration. In both countries, GI play an important role in contrasting land take and, for their adaptive and cross-scale nature, they help to generate a res ilient approach to urban plans and projects. Due to their fl exible and site-based nature, GI can be adapted, even if through different methodologies and approaches, both to urban and extra-urban contexts. On one hand, France, through its strong national policy on ecological networks, recognizes them as one of the major planning strategies toward a more sustainable development of territories; on the other hand, Italy has no national policy and Regions still have a hard time integrating them in already existing planning tools. In this perspective, Italian experimentations on GI construction appear to be a simple and sporadic add-on of urban and regional plans

Making Sense of Ethnocentrism: Intelligence Analysis & National Cultural Dimensions

Varying internal and external stimulants naturally oscillate the creation of objective intelligence analysis; however, the most egregious offender to accuracy and completeness is the natural human mental process. No element of intelligence analysis is more formidable than the cognitive process that houses specific deviations, known as biases, as it yields inaccuracies and alters what is believed to be a rational response to a complex analytical problem. The phenomenon of ethnocentrism is consistently identified as an analytical limitation of intelligence professionals, derived from cognitive bias. Ultimately, ethnocentrism manifests an analyst’s perception of information directly through the lens of culturally dependent heuristics and cognitive patterns accumulated over a lifetime. The application of the Six-Dimensions of National Culture (6-D model), put forth in 1980 by Geert Hofstede, was selected to alter this pattern via an exploratory qualitative multi-case study involving Imperial Japan (Pearl Harbor), the Soviet Union (Cuban Missile Crisis), and al-Qaeda before September 11, 2001. With the application of the 6-D model, in concert with the Data-Frame Theory, as presented by Moore and Hoffman, this dissertation attempts to amplify the human capacity to make sense of ethnocentrism by expanding analytical frames and, as a result, help analysts produce and disseminate more holistic intelligence. Research results identified significant divergence between the created cultural disposition and the US intelligence perspective, specifically throughout the IDV, MAS, and IVR cultural dimensions. This study highlights the implications of ethnocentrism within the intelligence paradigm and identifies the necessity to employ cultural condition frameworks when attempting to produce accurate and comprehensive intelligence

Across Space and Time. Papers from the 41st Conference on Computer Applications and Quantitative Methods in Archaeology, Perth, 25-28 March 2013

This volume presents a selection of the best papers presented at the forty-first annual Conference on Computer Applications and Quantitative Methods in Archaeology. The theme for the conference was "Across Space and Time", and the papers explore a multitude of topics related to that concept, including databases, the semantic Web, geographical information systems, data collection and management, and more

Geotechnical Engineering for the Preservation of Monuments and Historic Sites III

The conservation of monuments and historic sites is one of the most challenging problems facing modern civilization. It involves, in inextricable patterns, factors belonging to different fields (cultural, humanistic, social, technical, economical, administrative) and the requirements of safety and use appear to be (or often are) in conflict with the respect of the integrity of the monuments. The complexity of the topic is such that a shared framework of reference is still lacking among art historians, architects, structural and geotechnical engineers. The complexity of the subject is such that a shared frame of reference is still lacking among art historians, architects, architectural and geotechnical engineers. And while there are exemplary cases of an integral approach to each building element with its static and architectural function, as a material witness to the culture and construction techniques of the original historical period, there are still examples of uncritical reliance on modern technology leading to the substitution from earlier structures to new ones, preserving only the iconic look of the original monument. Geotechnical Engineering for the Preservation of Monuments and Historic Sites III collects the contributions to the eponymous 3rd International ISSMGE TC301 Symposium (Naples, Italy, 22-24 June 2022). The papers cover a wide range of topics, which include: 　 - Principles of conservation, maintenance strategies, case histories - The knowledge: investigations and monitoring - Seismic risk, site effects, soil structure interaction - Effects of urban development and tunnelling on built heritage - Preservation of diffuse heritage: soil instability, subsidence, environmental damages The present volume aims at geotechnical engineers and academics involved in the preservation of monuments and historic sites worldwide

Reports to the President

A compilation of annual reports including a report from the President of the Massachusetts Institute of Technology, as well as reports from the academic and administrative units of the Institute. The reports outline the year's goals, accomplishments, honors and awards, and future plans