21 research outputs found

    Trust based Privacy Policy Enforcement in Cloud Computing

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    Cloud computing offers opportunities for organizations to reduce IT costs by using the computation and storage of a remote provider. Despite the benefits offered by cloud computing paradigm, organizations are still wary of delegating their computation and storage to a cloud service provider due to trust concerns. The trust issues with the cloud can be addressed by a combination of regulatory frameworks and supporting technologies. Privacy Enhancing Technologies (PET) and remote attestation provide the technologies for addressing the trust concerns. PET provides proactive measures through cryptography and selective dissemination of data to the client. Remote attestation mechanisms provides reactive measures by enabling the client to remotely verify if a provider is compromised. The contributions of this work are three fold. This thesis explores the PET landscape by studying in detail the implications of using PET in cloud architectures. The practicality of remote attestation in Software as a Service (SaaS) and Infrastructure as a Service (IaaS) scenarios is also analyzed and improvements have been proposed to the state of the art. This thesis also propose a fresh look at trust relationships in cloud computing, where a single provider changes its configuration for each client based on the subjective and dynamic trust assessments of clients. We conclude by proposing a plan for expanding on the completed work

    TOWARDS ENHANCING SECURITY IN CLOUD STORAGE ENVIRONMENTS

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    Although widely adopted, one of the biggest concerns with cloud computing is how to preserve the security and privacy of client data being processed and/or stored in a cloud computing environment. When it comes to cloud data protection, the methods employed can be very similar to protecting data within a traditional data center. Authentication and identity, access control, encryption, secure deletion, integrity checking, and data masking are all data protection methods that have applicability in cloud computing. Current research in cloud data protection primarily falls into three main categories: 1) Authentication & Access Control, 2) Encryption, and 3) Intrusion Detection. This thesis examines the various mechanisms that currently exist to protect data being stored in a public cloud computing environment. It also looks at the methods employed to detect intrusions targeting cloud data when and if data protection mechanisms fail. In response to these findings, we present three primary contributions that focus on enhancing the overall security of user data residing in a hosted environment such as the cloud. We first provide an analysis of Cloud Storage vendors that shows how data can be exposed when shared - even in the most `secure' environments. Secondly, we o er Pretty Good Privacy (PGP) as a method of securing data within this environment while enhancing PGP'sWeb of Trust validation mechanism using Bitcoin. Lastly, we provide a framework for protecting data exfiltration attempts in Software-as-a-Service (SaaS) Cloud Storage environments using Cyber Deception

    Blockchain smart contracts: Applications, challenges, and future trends

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    In recent years, the rapid development of blockchain technology and cryptocurrencies has influenced the financial industry by creating a new crypto-economy. Then, next-generation decentralized applications without involving a trusted third-party have emerged thanks to the appearance of smart contracts, which are computer protocols designed to facilitate, verify, and enforce automatically the negotiation and agreement among multiple untrustworthy parties. Despite the bright side of smart contracts, several concerns continue to undermine their adoption, such as security threats, vulnerabilities, and legal issues. In this paper, we present a comprehensive survey of blockchain-enabled smart contracts from both technical and usage points of view. To do so, we present a taxonomy of existing blockchain-enabled smart contract solutions, categorize the included research papers, and discuss the existing smart contract-based studies. Based on the findings from the survey, we identify a set of challenges and open issues that need to be addressed in future studies. Finally, we identify future trends

    A Trust-by-Design Framework for the Internet of Things

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    The Internet of Things (IoT) is an environment where interconnected entities can interact and can be identifiable, usable, and controllable via the Internet. However, in order to interact among them, such IoT entities must trust each other. Trust is difficult to define because it concerns different aspects and is strongly dependent on the context. For this reason, a holistic approach allowing developers to consider and implement trust in the IoT is highly desirable. Nevertheless, trust is usually considered among different IoT entities only when they have to interact among them. In fact, without considering it during the whole System Developmente Life Cycle (SDLC) there is the possibility that security issues will be raised. In fact, without a clear conception of the possible threats during the development of the IoT entity, the lack of planning can be insufficient in order to protect the IoT entity. For this reason, we believe that it is fundamental to consider trust during the whole SDLC in order to carefully plan how an IoT entity will perform trust decisions and interact with the other IoT entities. To fulfill this goal, in this thesis work, we propose a trust-by-design framework for the IoT that is composed of a K-Model and several transversal activities. On the one hand, the K-Model covers the SDLC from the need phase to the utilization phase. On the other hand, the transversal activities will be implemented differently depending on the phases. A fundamental aspect that we implement in this framework is the relationship that trust has with other related domains such as security and privacy. Thus we will also consider such domains and their characteristics in order to develop a trusted IoT entity

    An interdisciplinary concept for human-centered explainable artificial intelligence - Investigating the impact of explainable AI on end-users

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    Since the 1950s, Artificial Intelligence (AI) applications have captivated people. However, this fascination has always been accompanied by disillusionment about the limitations of this technology. Today, machine learning methods such as Deep Neural Networks (DNN) are successfully used in various tasks. However, these methods also have limitations: Their complexity makes their decisions no longer comprehensible to humans - they are black-boxes. The research branch of Explainable AI (XAI) has addressed this problem by investigating how to make AI decisions comprehensible. This desire is not new. In the 1970s, developers of intrinsic explainable AI approaches, so-called white-boxes (e.g., rule-based systems), were dealing with AI explanations. Nowadays, with the increased use of AI systems in all areas of life, the design of comprehensible systems has become increasingly important. Developing such systems is part of Human-Centred AI (HCAI) research, which integrates human needs and abilities in the design of AI interfaces. For this, an understanding is needed of how humans perceive XAI and how AI explanations influence the interaction between humans and AI. One of the open questions concerns the investigation of XAI for end-users, i.e., people who have no expertise in AI but interact with such systems or are impacted by the system's decisions. This dissertation investigates the impact of different levels of interactive XAI of white- and black-box AI systems on end-users perceptions. Based on an interdisciplinary concept presented in this work, it is examined how the content, type, and interface of explanations of DNN (black box) and rule-based systems (white box) are perceived by end-users. How XAI influences end-users mental models, trust, self-efficacy, cognitive workload, and emotional state regarding the AI system is the centre of the investigation. At the beginning of the dissertation, general concepts regarding AI, explanations, and psychological constructs of mental models, trust, self-efficacy, cognitive load, and emotions are introduced. Subsequently, related work regarding the design and investigation of XAI for users is presented. This serves as a basis for the concept of a Human-Centered Explainable AI (HC-XAI) presented in this dissertation, which combines an XAI design approach with user evaluations. The author pursues an interdisciplinary approach that integrates knowledge from the research areas of (X)AI, Human-Computer Interaction, and Psychology. Based on this interdisciplinary concept, a five-step approach is derived and applied to illustrative surveys and experiments in the empirical part of this dissertation. To illustrate the first two steps, a persona approach for HC-XAI is presented, and based on that, a template for designing personas is provided. To illustrate the usage of the template, three surveys are presented that ask end-users about their attitudes and expectations towards AI and XAI. The personas generated from the survey data indicate that end-users often lack knowledge of XAI and that their perception of it depends on demographic and personality-related characteristics. Steps three to five deal with the design of XAI for concrete applications. For this, different levels of interactive XAI are presented and investigated in experiments with end-users. For this purpose, two rule-based systems (i.e., white-box) and four systems based on DNN (i.e., black-box) are used. These are applied for three purposes: Cooperation & collaboration, education, and medical decision support. Six user studies were conducted for this purpose, which differed in the interactivity of the XAI system used. The results show that end-users trust and mental models of AI depend strongly on the context of use and the design of the explanation itself. For example, explanations that a virtual agent mediates are shown to promote trust. The content and type of explanations are also perceived differently by users. The studies also show that end-users in different application contexts of XAI feel the desire for interactive explanations. The dissertation concludes with a summary of the scientific contribution, points out limitations of the presented work, and gives an outlook on possible future research topics to integrate explanations into everyday AI systems and thus enable the comprehensible handling of AI for all people.Seit den 1950er Jahren haben Anwendungen der Künstlichen Intelligenz (KI) die Menschen in ihren Bann gezogen. Diese Faszination wurde jedoch stets von Ernüchterung über die Grenzen dieser Technologie begleitet. Heute werden Methoden des maschinellen Lernens wie Deep Neural Networks (DNN) erfolgreich für verschiedene Aufgaben eingesetzt. Doch auch diese Methoden haben ihre Grenzen: Durch ihre Komplexität sind ihre Entscheidungen für den Menschen nicht mehr nachvollziehbar - sie sind Black-Boxes. Der Forschungszweig der Erklärbaren KI (engl. XAI) hat sich diesem Problem angenommen und untersucht, wie man KI-Entscheidungen nachvollziehbar machen kann. Dieser Wunsch ist nicht neu. In den 1970er Jahren beschäftigten sich die Entwickler von intrinsisch erklärbaren KI-Ansätzen, so genannten White-Boxes (z. B. regelbasierte Systeme), mit KI-Erklärungen. Heutzutage, mit dem zunehmenden Einsatz von KI-Systemen in allen Lebensbereichen, wird die Gestaltung nachvollziehbarer Systeme immer wichtiger. Die Entwicklung solcher Systeme ist Teil der Menschzentrierten KI (engl. HCAI) Forschung, die menschliche Bedürfnisse und Fähigkeiten in die Gestaltung von KI-Schnittstellen integriert. Dafür ist ein Verständnis darüber erforderlich, wie Menschen XAI wahrnehmen und wie KI-Erklärungen die Interaktion zwischen Mensch und KI beeinflussen. Eine der offenen Fragen betrifft die Untersuchung von XAI für Endnutzer, d.h. Menschen, die keine Expertise in KI haben, aber mit solchen Systemen interagieren oder von deren Entscheidungen betroffen sind. In dieser Dissertation wird untersucht, wie sich verschiedene Stufen interaktiver XAI von White- und Black-Box-KI-Systemen auf die Wahrnehmung der Endnutzer auswirken. Basierend auf einem interdisziplinären Konzept, das in dieser Arbeit vorgestellt wird, wird untersucht, wie der Inhalt, die Art und die Schnittstelle von Erklärungen von DNN (Black-Box) und regelbasierten Systemen (White-Box) von Endnutzern wahrgenommen werden. Wie XAI die mentalen Modelle, das Vertrauen, die Selbstwirksamkeit, die kognitive Belastung und den emotionalen Zustand der Endnutzer in Bezug auf das KI-System beeinflusst, steht im Mittelpunkt der Untersuchung. Zu Beginn der Arbeit werden allgemeine Konzepte zu KI, Erklärungen und psychologische Konstrukte von mentalen Modellen, Vertrauen, Selbstwirksamkeit, kognitiver Belastung und Emotionen vorgestellt. Anschließend werden verwandte Arbeiten bezüglich dem Design und der Untersuchung von XAI für Nutzer präsentiert. Diese dienen als Grundlage für das in dieser Dissertation vorgestellte Konzept einer Menschzentrierten Erklärbaren KI (engl. HC-XAI), das einen XAI-Designansatz mit Nutzerevaluationen kombiniert. Die Autorin verfolgt einen interdisziplinären Ansatz, der Wissen aus den Forschungsbereichen (X)AI, Mensch-Computer-Interaktion und Psychologie integriert. Auf der Grundlage dieses interdisziplinären Konzepts wird ein fünfstufiger Ansatz abgeleitet und im empirischen Teil dieser Arbeit auf exemplarische Umfragen und Experimente und angewendet. Zur Veranschaulichung der ersten beiden Schritte wird ein Persona-Ansatz für HC-XAI vorgestellt und darauf aufbauend eine Vorlage für den Entwurf von Personas bereitgestellt. Um die Verwendung der Vorlage zu veranschaulichen, werden drei Umfragen präsentiert, in denen Endnutzer zu ihren Einstellungen und Erwartungen gegenüber KI und XAI befragt werden. Die aus den Umfragedaten generierten Personas zeigen, dass es den Endnutzern oft an Wissen über XAI mangelt und dass ihre Wahrnehmung dessen von demografischen und persönlichkeitsbezogenen Merkmalen abhängt. Die Schritte drei bis fünf befassen sich mit der Gestaltung von XAI für konkrete Anwendungen. Hierzu werden verschiedene Stufen interaktiver XAI vorgestellt und in Experimenten mit Endanwendern untersucht. Zu diesem Zweck werden zwei regelbasierte Systeme (White-Box) und vier auf DNN basierende Systeme (Black-Box) verwendet. Diese werden für drei Zwecke eingesetzt: Kooperation & Kollaboration, Bildung und medizinische Entscheidungsunterstützung. Hierzu wurden sechs Nutzerstudien durchgeführt, die sich in der Interaktivität des verwendeten XAI-Systems unterschieden. Die Ergebnisse zeigen, dass das Vertrauen und die mentalen Modelle der Endnutzer in KI stark vom Nutzungskontext und der Gestaltung der Erklärung selbst abhängen. Es hat sich beispielsweise gezeigt, dass Erklärungen, die von einem virtuellen Agenten vermittelt werden, das Vertrauen fördern. Auch der Inhalt und die Art der Erklärungen werden von den Nutzern unterschiedlich wahrgenommen. Die Studien zeigen zudem, dass Endnutzer in unterschiedlichen Anwendungskontexten von XAI den Wunsch nach interaktiven Erklärungen verspüren. Die Dissertation schließt mit einer Zusammenfassung des wissenschaftlichen Beitrags, weist auf Grenzen der vorgestellten Arbeit hin und gibt einen Ausblick auf mögliche zukünftige Forschungsthemen, um Erklärungen in alltägliche KI-Systeme zu integrieren und damit den verständlichen Umgang mit KI für alle Menschen zu ermöglichen

    Data justice and the right to the city

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    Agoric computation: trust and cyber-physical systems

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    In the past two decades advances in miniaturisation and economies of scale have led to the emergence of billions of connected components that have provided both a spur and a blueprint for the development of smart products acting in specialised environments which are uniquely identifiable, localisable, and capable of autonomy. Adopting the computational perspective of multi-agent systems (MAS) as a technological abstraction married with the engineering perspective of cyber-physical systems (CPS) has provided fertile ground for designing, developing and deploying software applications in smart automated context such as manufacturing, power grids, avionics, healthcare and logistics, capable of being decentralised, intelligent, reconfigurable, modular, flexible, robust, adaptive and responsive. Current agent technologies are, however, ill suited for information-based environments, making it difficult to formalise and implement multiagent systems based on inherently dynamical functional concepts such as trust and reliability, which present special challenges when scaling from small to large systems of agents. To overcome such challenges, it is useful to adopt a unified approach which we term agoric computation, integrating logical, mathematical and programming concepts towards the development of agent-based solutions based on recursive, compositional principles, where smaller systems feed via directed information flows into larger hierarchical systems that define their global environment. Considering information as an integral part of the environment naturally defines a web of operations where components of a systems are wired in some way and each set of inputs and outputs are allowed to carry some value. These operations are stateless abstractions and procedures that act on some stateful cells that cumulate partial information, and it is possible to compose such abstractions into higher-level ones, using a publish-and-subscribe interaction model that keeps track of update messages between abstractions and values in the data. In this thesis we review the logical and mathematical basis of such abstractions and take steps towards the software implementation of agoric modelling as a framework for simulation and verification of the reliability of increasingly complex systems, and report on experimental results related to a few select applications, such as stigmergic interaction in mobile robotics, integrating raw data into agent perceptions, trust and trustworthiness in orchestrated open systems, computing the epistemic cost of trust when reasoning in networks of agents seeded with contradictory information, and trust models for distributed ledgers in the Internet of Things (IoT); and provide a roadmap for future developments of our research

    ECONOMICALLY PROTECTING COMPLEX, LEGACY OPERATING SYSTEMS USING SECURE DESIGN PRINCIPLES

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    In modern computer systems, complex legacy operating systems, such as Linux, are deployed ubiquitously. Many design choices in these legacy operating systems predate a modern understanding of security risks. As a result, new attack opportunities are routinely discovered to subvert such systems, which reveal design flaws that spur new research about secure design principles and other security mechanisms to thwart these attacks. Most research falls into two categories: encapsulating the threat and redesigning the system from scratch. Each approach has its challenge. Encapsulation can only limit the exposure to the risk, but not entirely prevent it. Rewriting the huge codebase of these operating systems is impractical in terms of developer effort, but appealing inasmuch as it can comprehensively eliminate security risks. This thesis pursues a third, understudied option: retrofitting security design principles in the existing kernel design. Conventional wisdom discourages retrofitting security because retrofitting is a hard problem, may require the use of new abstractions or break backward compatibility, may have unforeseen consequences, and may be equivalent to redesigning the system from scratch in terms of effort. This thesis offers new evidence to challenge this conventional wisdom, indicating that one can economically retrofit a comprehensive security policy onto complex, legacy systems. To demonstrate this assertion, this thesis firstly surveys the alternative of encapsulating the threat to the complex, legacy system by adding a monitoring layer using a technique called Virtual Machine Introspection, and discusses the shortcomings of this technique. Secondly, this thesis shows how to enforce the principle of least privilege by removing the need to run setuid-to-root binaries with administrator privilege. Finally, this thesis takes the first steps to show how to economically retrofit secure design principles to the OS virtualization feature of the Linux kernel called containers without rewriting the whole system. This approach can be applied more generally to other legacy systems.Doctor of Philosoph

    It's getting crowded! : improving the effectiveness of microtask crowdsourcing

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    Junos OS Security Configuration Guide

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    This preface provides the following guidelines for using the Junos OS Security Configuration Guide: • J Series and SRX Series Documentation and Release Notes on page xli • Objectives on page xlii • Audience on page xlii • Supported Routing Platforms on page xlii • Document Conventions on page xlii • Documentation Feedback on page xliv • Requesting Technical Support on page xliv Juniper Networks supports a technical book program to publish books by Juniper Networks engineers and subject matter experts with book publishers around the world. These books go beyond the technical documentation to explore the nuances of network architecture, deployment, and administration using the Junos operating system (Junos OS) and Juniper Networks devices. In addition, the Juniper Networks Technical Library, published in conjunction with O'Reilly Media, explores improving network security, reliability, and availability using Junos OS configuration techniques. All the books are for sale at technical bookstores and book outlets around the world. The current list can be viewed at http://www.juniper.net/books .Junos OS for SRX Series Services Gateways integrates the world-class network security and routing capabilities of Juniper Networks. Junos OS includes a wide range of packet-based filtering, class-of-service (CoS) classifiers, and traffic-shaping features as well as a rich, extensive set of flow-based security features including policies, screens, network address translation (NAT), and other flow-based services. Traffic that enters and exits services gateway is processed according to features you configure, such as packet filters, security policies, and screens. For example, the software can determine: • Whether the packet is allowed into the device • Which firewall screens to apply to the packet • The route the packet takes to reach its destination • Which CoS to apply to the packet, if any • Whether to apply NAT to translate the packet’s IP address • Whether the packet requires an Application Layer Gateway (ALG
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