51 research outputs found

    Resource accounting and reservation in Java Virtual Machine

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    The Java platform The Java programming language was designed to developed small application for embedded devices, but it was a long time ago. Today, Java application are running in many platforms ranging from smartphones to enterprise servers. Modern pervasive middleware is typically implemented using Java because of its safety, flexibility, and mature development environment. However, the Java virtual machine specification has not had a major revised since 1999 Several researches had addressed these important issues. As result of these efforts some Java specification requests (JSR) have emerged. We consider there are seven JSRs relate to monitoring and to resource accounting and reservation: three for the Java Management eXtension API (JSRs 3, 160, 255), two for Metric Instrumentation (JSRs 138, 174) and two for resource-consumption management (JSRs 121, 284). The Java Management extension API only addresses monitoring and management: it does not define specific resource accounting or reservation strategies. JSRs 138 and 174 define monitors for the Java Virtual Machine. They are coarse grained, monitoring the number of running threads, the memory used, the number of garbage collections and so on. They monitor the entire virtual machine, not specific component so, they are useless to most middleware. Based on the Multitasking Virtual Machin

    COTS GIS Integration and its Soap-Based Web Services

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    In the modern geographic information systems, COTS software has been playing a major role. However, deploying heterogeneous GIS software has the tendency to form fragmented data sets and to cause inconsistency. To accomplish data consolidation, we must achieve interoperability between different GIS tools. In my thesis project, I developed Vector and Raster Data Adapters to implement the spatial data consolidation. I deployed ArcIMS to publish the spatial data and metadata onto Internet. Furthermore, the SOAP-Based GIS Web services are implemented to achieve the enterprise information system integration. The contribution of ours in this project is we have streamlined the COTS GIS server, the J2EE coordinator server, the web service provider components, and the COTS web publishing tools into a hybrid web service architecture, in which the enterprise information system integration, the web publishing, and the business-to business online services are uniformed

    Alternative Java Security Policy Model

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    Récemment, les systèmes distribués sont devenus une catégorie fondamentale de systèmes informatiques. Par conséquent, leur sécurité est devenue essentielle. La recherche décrite dans ce document vise à apporter un éclaircissement sur leurs vulnérabilités quant à la sécurité. Pour ce faire, on a examiné les propriétés de sécurité qu'un système distribué considéré sécuritaire doit supporter. En cherchant un système avec lequel travailler, on a étudié des failles de sécurité des systèmes distribués existants. On a étudié la sécurité de Java et des outils utilisés pour sécuriser ces systèmes. Suite à ces recherches, un nouveau modèle de sécurité Java imposant de nouvelles propriétés de sécurité a été développé. Ce document commence par les résultats de notre recherche sur les systèmes distribués, les outils de sécurité, et la sécurité de Java. Ensuite, on décrit les détails du nouveau système pour finalement faire la démonstration des améliorations qu'apporte ce système avec un exemple.Recently, distributed systems have become a fundamental type of computer system. Because of this, their security is essential. The research described in this document aimed to find their weaknesses and to find the means to improve them with regards to their security. To do that, we examined the security properties that a system considered secure must support. While looking for a system with which we could work, we studied security problems in existing distributed systems. We studied the security of Java and some tools used to secure these systems. Following our research, we developed a new Java security model, which imposed new security properties. This document begins with the results of our research in distributed systems, security tools, and Java security. Next, we go into detail about our new system to finally demonstrate the security enhancements of our system using an example

    COTS GIS Integration and its Soap-Based Web Services

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    In the modern geographic information systems, COTS software has been playing a major role. However, deploying heterogeneous GIS software has the tendency to form fragmented data sets and to cause inconsistency. To accomplish data consolidation, we must achieve interoperability between different GIS tools. In my thesis project, I developed Vector and Raster Data Adapters to implement the spatial data consolidation. I deployed ArcIMS to publish the spatial data and metadata onto Internet. Furthermore, the SOAP-Based GIS Web services are implemented to achieve the enterprise information system integration. The contribution of ours in this project is we have streamlined the COTS GIS server, the J2EE coordinator server, the web service provider components, and the COTS web publishing tools into a hybrid web service architecture, in which the enterprise information system integration, the web publishing, and the business-to business online services are uniformed

    On the cloud deployment of a session abstraction for service/data aggregation

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    Dissertação para obtenção do Grau de Mestre em Engenharia InformáticaThe global cyber-infrastructure comprehends a growing number of resources, spanning over several abstraction layers. These resources, which can include wireless sensor devices or mobile networks, share common requirements such as richer inter-connection capabilities and increasing data consumption demands. Additionally, the service model is now widely spread, supporting the development and execution of distributed applications. In this context, new challenges are emerging around the “big data” topic. These challenges include service access optimizations, such as data-access context sharing, more efficient data filtering/ aggregation mechanisms, and adaptable service access models that can respond to context changes. The service access characteristics can be aggregated to capture specific interaction models. Moreover, ubiquitous service access is a growing requirement, particularly regarding mobile clients such as tablets and smartphones. The Session concept aggregates the service access characteristics, creating specific interaction models, which can then be re-used in similar contexts. Existing Session abstraction implementations also allow dynamic reconfigurations of these interaction models, so that the model can adapt to context changes, based on service, client or underlying communication medium variables. Cloud computing on the other hand, provides ubiquitous access, along with large data persistence and processing services. This thesis proposes a Session abstraction implementation, deployed on a Cloud platform, in the form of a middleware. This middleware captures rich/dynamic interaction models between users with similar interests, and provides a generic mechanism for interacting with datasources based on multiple protocols. Such an abstraction contextualizes service/users interactions, can be reused by other users in similar contexts. This Session implementation also permits data persistence by saving all data in transit in a Cloud-based repository, The aforementioned middleware delivers richer datasource-access interaction models, dynamic reconfigurations, and allows the integration of heterogenous datasources. The solution also provides ubiquitous access, allowing client connections from standard Web browsers or Android based mobile devices

    Programming language abstractions for mobile code

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    Scala is a general-purpose programming language developed at EPFL. It combines the most important concepts found in object-oriented and functional languages. Scala is a statically typed language; in particular it features an advanced type system and supports local type inference. Furthermore it integrates well with the Java and .net platforms: their libraries are accessible without glue code and the Scala compiler generates code for both execution environments. The Scala programming language has several features that make it desirable as a language for distributed application programming. In particular, it supports first-class functions which are useful in relation with the notions of distributed scope and code mobility. In that context, the missing support for run-time types is one important drawback of the Java run-time environment as a target platform. This thesis focuses on the realisation of a new concept combining essential notions from the functional and distributed programming and implying the extension of the notion of lexical scoping to the distributed context. In short, we claim that the notion of lambda abstraction provides an elegant way for dealing with the dynamic rebinding of local references in a distributed execution environment. The key ideas exposed in this research work have been implemented in our Scala compiler. This helped us to evaluate the used techniques, in particular their impact on the reliability and the performance of distributed programs. So far, most research works related to the present subject have focused on functional programming languages, in particular on the ML language family

    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

    Developing Materials Informatics Workbench for Expediting the Discovery of Novel Compound Materials

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    A distributed hard real-time Java system for high mobility components

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    In this work we propose a methodology for providing real-time capabilities to component-based, on-the-fly reconfigurable, distributed systems. In such systems, software components migrate across computational resources at run-time to allow applications to adapt to changes in user requirements or to external events. We describe how we achieve run-time reconfiguration in distributed Java applications by appropriately migrating servers. Guaranteed-rate schedulers at the servers provide the necessary temporal protection and so simplify remote method invocation management. We describe how we manage overhead and resource utilization by controlling the parameters of the server schedulers. According to our measurements, this methodology provides real-time capability to component-based reconfigurable distributed systems in an effcient and effective way. In addition, we propose a new resource discovery protocol, REALTOR, which is based on a combination of pull-based and push-based resource information dissemination. REALTOR has been designed for real-time component-based distributed applications in very dynamic or adverse environments. REALTOR supports survivability and information assurance by allowing the migration of components to safe locations under emergencies suchas externalattack, malfunction, or lackofresources. Simulation studies show that under normal and heavy load conditions REALTOR remains very effective in finding available resources, and does so with a reasonably low communication overhead.REALTOR 1)effectively locates resources under highly dynamic conditions, 2) has an overhead that is system-size independent, and 3) works well in highlyadverse environments.We evaluate the effectiveness of a REALTOR implementation as part of Agile Objects, an infrastructure for real-time capable, highly mobile Java components
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