336 research outputs found

    Droplet: Decentralized Authorization for IoT Data Streams

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    This paper presents Droplet, a decentralized data access control service, which operates without intermediate trust entities. Droplet enables data owners to securely and selectively share their encrypted data while guaranteeing data confidentiality against unauthorized parties. Droplet's contribution lies in coupling two key ideas: (i) a new cryptographically-enforced access control scheme for encrypted data streams that enables users to define fine-grained stream-specific access policies, and (ii) a decentralized authorization service that handles user-defined access policies. In this paper, we present Droplet's design, the reference implementation of Droplet, and experimental results of three case-study apps atop of Droplet: Fitbit activity tracker, Ava health tracker, and ECOviz smart meter dashboard

    Cloaking fabric, a confidentiality layer for hyperledger fabric

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    Permissioned blockchains have resulted in some unlikely collaborations between organizations that would have previously been impossible due them mutually distrusting each other. They provide a sense of trust among the parties due to the decentralized nature of their deployment that prevents censorship from a subset of the parties. Decentralization mandates that all the parties have the same view of the system, therefore it has been difficult to represent and store private data. Asynchronous Verifiable Secret Sharing(AVSS) and Secure Multi Party Computation(MPC) are techniques from cryptography that allow the sharing of secrets among multiple parties and enable arbitrary computations on the shared data without leaking any information about the data. Previously, AVSS and MPC protocols were inefficient for practical use or did not work in the same setting of blockchains where nodes of the blockchain could arbitrarily fail. Honeybadger AVSS and Honeybadger MPC are robust and scalable frameworks that make them a good candidate to be coupled with a permissioned blockchain to form a confidentiality layer on top of it. We present Cloaking Fabric, an extension to the popular permissioned blockchain Hyperledger Fabric that utilizes HoneybadgerMPC and HoneybadgerAVSS to provide a confidentiality layer that would allow smart-contracts on the blockchain to interact with private data. We present a suite of applications to demonstrate our system and measure the overhead it would have over standard MPC operations

    State-of-the-Art in Data Integrity and Privacy-Preserving in Cloud Computing

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    Cloud computing (CC) is a fast-growing technology that offers computers, networking, and storage services that can be accessed and used over the internet. Cloud services save users money because they are pay-per-use, and they save time because they are on-demand and elastic, a unique aspect of cloud computing. However, several security issues must be addressed before users store data in the cloud. Because the user will have no direct control over the data that has been outsourced to the cloud, particularly personal and sensitive data (health, finance, military, etc.), and will not know where the data is stored, the user must ensure that the cloud stores and maintains the outsourced data appropriately. The study's primary goals are to make the cloud and data security challenges more understandable, to briefly explain the techniques used to achieve privacy and data integrity, to compare various recent studies in both pre-quantum and post-quantum, and to focus on current gaps in solving privacy and data integrity issues

    A smart TCP socket for distributed computing

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    Master'sMASTER OF SCIENC

    Near Field Communication: From theory to practice

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    This book provides the technical essentials, state-of-the-art knowledge, business ecosystem and standards of Near Field Communication (NFC)by NFC Lab - Istanbul research centre which conducts intense research on NFC technology. In this book, the authors present the contemporary research on all aspects of NFC, addressing related security aspects as well as information on various business models. In addition, the book provides comprehensive information a designer needs to design an NFC project, an analyzer needs to analyze requirements of a new NFC based system, and a programmer needs to implement an application. Furthermore, the authors introduce the technical and administrative issues related to NFC technology, standards, and global stakeholders. It also offers comprehensive information as well as use case studies for each NFC operating mode to give the usage idea behind each operating mode thoroughly. Examples of NFC application development are provided using Java technology, and security considerations are discussed in detail. Key Features: Offers a complete understanding of the NFC technology, including standards, technical essentials, operating modes, application development with Java, security and privacy, business ecosystem analysis Provides analysis, design as well as development guidance for professionals from administrative and technical perspectives Discusses methods, techniques and modelling support including UML are demonstrated with real cases Contains case studies such as payment, ticketing, social networking and remote shopping This book will be an invaluable guide for business and ecosystem analysts, project managers, mobile commerce consultants, system and application developers, mobile developers and practitioners. It will also be of interest to researchers, software engineers, computer scientists, information technology specialists including students and graduates.Publisher's Versio

    Fault-tolerant dynamic parallel schedules

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    Dynamic Parallel Schedules (DPS) is a high-level framework for developing parallel applications on distributed memory computers such as clusters of PCs. DPS applications are defined by using directed acyclic flow graphs composed of user-defined operations. These operations derive from basic concepts provided by the framework: split, merge, leaf and stream operations. Whereas a simple parallel application can be expressed with a split-leaf-merge sequence of operations, flow graphs of arbitrary complexity can be created. DPS provides run-time support for dynamically mapping flow graph operations onto the nodes of a cluster. The flow graph based application description used in DPS allows the framework to offer many additional features, most of these transparently to the application developer. In order to maximize performance, DPS applications benefit from automatic overlapping of computations and communications and from implicit pipelining. The framework provides simple primitives for flow control and load balancing. Applications can integrate flow graph parts provided by other applications as parallel components. Since the mapping of DPS applications to processing nodes can be dynamically changed at runtime, DPS provides a basis for developing malleable applications. The DPS framework provides a complete fault tolerance mechanism based on the dynamic mapping capabilities, ensuring continued execution of parallel applications even in the presence of multiple node failures. DPS is provided as an open-source, cross-platform C++ library allowing DPS applications and services to run on heterogeneous clusters

    Privacy-preserving E-ticketing Systems for Public Transport Based on RFID/NFC Technologies

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    Pervasive digitization of human environment has dramatically changed our everyday lives. New technologies which have become an integral part of our daily routine have deeply affected our perception of the surrounding world and have opened qualitatively new opportunities. In an urban environment, the influence of such changes is especially tangible and acute. For example, ubiquitous computing (also commonly referred to as UbiComp) is a pure vision no more and has transformed the digital world dramatically. Pervasive use of smartphones, integration of processing power into various artefacts as well as the overall miniaturization of computing devices can already be witnessed on a daily basis even by laypersons. In particular, transport being an integral part of any urban ecosystem have been affected by these changes. Consequently, public transport systems have undergone transformation as well and are currently dynamically evolving. In many cities around the world, the concept of the so-called electronic ticketing (e-ticketing) is being extensively used for issuing travel permissions which may eventually result in conventional paper-based tickets being completely phased out already in the nearest future. Opal Card in Sydney, Oyster Card in London, Touch & Travel in Germany and many more are all the examples of how well the e-ticketing has been accepted both by customers and public transport companies. Despite numerous benefits provided by such e-ticketing systems for public transport, serious privacy concern arise. The main reason lies in the fact that using these systems may imply the dramatic multiplication of digital traces left by individuals, also beyond the transport scope. Unfortunately, there has been little effort so far to explicitly tackle this issue. There is still not enough motivation and public pressure imposed on industry to invest into privacy. In academia, the majority of solutions targeted at this problem quite often limit the real-world pertinence of the resultant privacy-preserving concepts due to the fact that inherent advantages of e-ticketing systems for public transport cannot be fully leveraged. This thesis is aimed at solving the aforementioned problem by providing a privacy-preserving framework which can be used for developing e-ticketing systems for public transport with privacy protection integrated from the outset. At the same time, the advantages of e-ticketing such as fine-grained billing, flexible pricing schemes, and transparent use (which are often the main drivers for public to roll out such systems) can be retained

    Impressions of Montserrat : a partial account of contesting realities on a British dependent territory

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    This thesis portrays a diversity of impressions of Montserrat, a British Dependent Territory (BDT) in the Eastern Caribbean. The thesis is a postmodern rejection of Grand Theory in the Social Sciences. First I interrogate the nature of social anthropology, both its theoretical and methodological assumptions. I then establish my own anthropology which is postmodern - partial, relative, uncomfortable and uncertain, and above all, impressionistic. The substantial chapters in the thesis support this postmodern impressionistic anthropology by referring to an ethnographic encounter with the competing and highly contested realities expressed by myself, some Montserratian poets, some calypsonians, some development workers, some local Montserratians, some tourists and the Montserratian Government and Tourist Board, and some travel writers. More precisely, the Preface reviews social anthropology as an uncomfortable and uncertain discipline. It also establishes and justifies my postmodern impressionistic anthropology which is thereafter illustrated by ethnographic vignettes in the following chapters. Via the anthropologist's impressions. Chapter One introduces the reader to the place and people of Montserrat. In Chapter Two, Montserrat is filtered through poets' impressions of the island and islanders, namely through the poets of the Maroons Creative Writing Group which is led by Dr. Howard Fergus. Chapter Three goes on to show that impressions of Montserrat, despite their highly contested nature, can be held not just singularly - as in the case of individual poets, but also plurally - as constellations such as the contrasting world-views of Montserratians and development workers on Montserrat. Chapters Four and Five continue my ethnographic impressions of Montserrat by presenting, respectively, the labours of several calypsonians on Montserrat who seek public recognition for their work, and, union leader, Chedmond Browne's struggle to maintain the trade union workers' employment at Plymouth Port. The final two chapters - Chapter Six and Chapter Seven - recede (ethnographically) from Montserrat: the first by considering the competing impressions and controversial histories of St. Patrick's Day, an annual celebration and commemoration on Montserrat; and the second by presenting a diverse selection of travel writers' impressions of Montserrat. The contentious content of both chapters affirms and reinforces the need for my postmodern and impressionistic approach to an anthropological investigation on Montserrat. Finally, the Conclusion to the thesis sums up the aforementioned chapters and makes general comments towards establishing a reflexive and sustainable postmodern impressionistic anthropology
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