Le modèle pair à pair (P2P) est aujourd'hui utilisé dans des environnements contraints. Néanmoins, pour pouvoir garantir un niveau de service, il requiert l'intégration d'une infrastructure de supervision adaptée. Ce dernier point constitue le cadre de notre travail. Concernant la modélisation de l'information de gestion, nous avons conçu une extension de CIM pour le modèle P2P. Pour la valider, nous l'avons implantée sur Jxta. Nous avons ensuite spécialisé notre modèle de l'information pour les tables de hachage distribuées (DHT). Nous avons abstrait le fonctionnement des DHTs, proposé un ensemble de métriques qui caractérisent leur performance, et déduit un modèle de l'information qui les intègre. Enfin, concernant l'organisation du plan de gestion, nous avons proposé un modèle hiérarchique, qui permet aux pairs de s'organiser selon une arborescence de gestionnaires et d'agents. Cette proposition a été mise en oeuvre sur une implantation de Pastry.

Ce manuscrit décrit les travaux de recherche que nous avons mené pendant les six dernières années sur le thème du partage transparent des données réparties à grande échelle. L'infrastructure visée a été celle des grilles de calcul. Notre objectif a été de répondre à la question: comment serait-il possible de construire un système fournissant un modèle transparent d'accès aux données, tout en tenant compte des contraintes spécifiques aux infrastructures physiques utilisées (architecture hiérarchique, distribution à grande échelle, volatilité, tolérance aux défaillances, etc.)? En réponse à ce défi, nous avons proposé le concept de service de partage de données pour grilles, pour lequel nous avons défini une spécification, une architecture et une mise en oeuvre. Ce travail se situe à la frontière de plusieurs domaines: systèmes à mémoire virtuellement partagée, systèmes pair-à-pair, systèmes tolérants aux fautes. En nous appuyant sur des résultats déjà existants qui proposaient des solutions partielles à notre problème, notre approche a consisté à étendre, adapter et coupler ces solutions partielles et à rajouter les "briques" manquantes, afin de construire une solution globale, plus complexe, mais qui satisfasse l'ensemble des propriétés recherchées. Un résultat issu de cette approche est la notion de groupe hiérarchique auto-organisant, qui combine des protocoles de cohérence issus des systèmes à mémoire virtuellement partagée avec des protocoles de gestion de groupe tolérants aux fautes. Sur cette notion repose notre approche pour la définition de protocoles de cohérence tolérants aux fautes, adaptés aux grilles. Nous avons attaché une importance particulière à la validation expérimentale} de notre proposition par une mise en oeuvre et par une évaluation sur des plates-formes réelles à travers des prototypes expérimentaux. Ceci nous a permis de réaliser des expériences multisites en grandeur nature sur la plate-forme Grid'5000, avec l'objectif d'évaluer les bénéfices apportés par notre service de partage de données aux environnements de calcul réparti sur grille. A cet effet, nous avons évalué la capacité de JuxMem à s'intégrer avec plusieurs modèles de programmation pour grille d'une part (GridRPC, modèles à base de composants) et avec d'autres technologies de stockage d'autre part (Gfarm, ASSIST). Cette intégration a été réalisée en collaboration avec des équipes françaises, telles que les équipes-projets REGAL et GRAAL de l'INRIA, mais aussi avec des équipes étrangères des universités de Pise et de Calabre en Italie, d'Illinois/Urbana-Champaign aux Etats-Unis et de Tsukuba au Japon. Enfin, nous avons travaillé en étroite concertation avec l'équipe JXTA de Sun Microsystems (Santa Clara, Etats-Unis), qui a soutenu nos efforts à travers un contrat de collaboration industrielle.

Today, Peer-to-peer (P2P) computing and Web Services play an important role in networking and computing. P2P computing, that aims addressing all the resources in a network and sharing them, is an old paradigm that gains importance nowadays with the advent of popular file sharing and instant messaging applications. On the other hand, a Web service is a software system that has an interface allowing applications to interact with other applications through Internet or intranet. Providing methods for publishing and discovering Web services from which mobile devices can facilitate in a P2P environment enables exploitation of P2P and Web service technologies efficiently by mobile devices. This also extends the range of devices that facilitate P2P and Web services technologies from servers and desktop computers to personal digital assistants (PDAs) and mobile phones. In this thesis, an architecture that enables publishing and discovering Web services for mobile clients that are inter-connected in a P2P environment is introduced. Key issues in this architecture are allowing mobile devices to join in a P2P network group, publishing Web services and discovering these services in P2P network. Invoking Web services that are published and discovered is another key issue in this architecture. The architecture introduced exploits P2P and Web services standards using various tools for mobile devices. For the purpose of organizing a P2P environment, JXTA protocols and services are used. WSDL is used for describing Web services. JXTA advertisements help in publication and discovery of Web services / and BPEL enables composition, deployment and execution of Web services. The architecture introduced within the scope of this thesis combines all these standards with tools that enable use of these standards on mobile devices. The work done in this thesis is realized as a part of Artemis, a project funded by European Commission for providing interoperability of medical information systems.

Recent developments in embedded systems give robots access to the Internet and make them more flexible and capable of performing more complex applications. However, these robots are still limited in terms of size, CPU power, storage resources and memory. Consequently, these robots have only been manufactured for certain specific applications and cannot be re-used for other applications. This presents us with a challenge to design a software framework - Robot Colony. The Robot Colony enables robots to be suitable for a wide range of applications, not originally received from manufacturers, to achieve greater functionality, flexibility and utility. This research outlines the architecture and functionality of the Robot Colony to support the collaboration between devices in the P2P community and also analyse the JXTA platform, which was the framework originally proposed. Lastly we present a customized P2P architecture that specifically addresses the interaction betweensoftware components across the network. We further discuss the following technologies applied in theframework: * XML-based Directory Service Provider * HTTP-based publish/describe control commands * Remote Process Invoke To fully complete the project, a thorough evaluation of the framework based on either the JXTAplatform or the customized P2P channel has been conducted. This evaluation provides basic statistics data for the proposed framework design and implementation. Further more, we have presented a realtime Demo at the Smart Device lab of the Queensland University of Technology.

eHealth is an emerging area that boosts up with advancement in Information and Communication Technology (ICT). Due to variety of eHealth solutions developed by different IT firms with no proper shared standards, interoperability issue is then raised. Blekinge County healthcare organizations use two different systems MAGNA CURA and SYStem Cross. The two systems work well in their own scope. But these systems often need to communicate and coordinate for exchange of patients’ information which leads to the problem of interoperability. The aim of this research study is to provide fast and reliable peer-to-peer solution for exchange of patient information so as to achieve interoperability among healthcare organizations. This proposed solution is tested as a middleware between MAGNA CURA and SYStem Cross currently used by Blekinge County healthcare organizations. A qualitative approach including in-depth literature review and a semi-structured face-to-face interview has been used for understanding the context of research problem. We have tested our approach through an executable prototype. The prototype is implemented using JXTA platform. We have learned that Blekinge healthcare is decentralized and heterogonous in nature. For such kind of environment, peer-to-peer communication approach is suggested. According to the test result, the suggested syntactic level interoperability between the two mentioned systems has been achieved.

Abstract - Mobile devices in the near future will need to collaborate to fulfill their function. Collaboration will be done by communication. We use a real world example of robotic soccer to come up with the necessary structures required for robotic communication. A review of related work is done and it is found no examples come close to providing a RANET. The robotic ad hoc network (RANET) we suggest uses existing structures pulled from the areas of wireless networks, peer to peer and software life-cycle management. Gaps are found in the existing structures so we describe how to extend some structures to satisfy the design. The RANET design supports robot cooperation by exchanging messages, discovering needed skills that other robots on the network may possess and the transfer of these skills. The network is built on top of a Bluetooth wireless network and uses JXTA to communicate and transfer skills. OSGi bundles form the skills that can be transferred. To test the nal design a reference implementation is done. Deficiencies in some third party software is found, specifically JXTA and JamVM and GNU Classpath. Lastly we look at how to fix the deciencies by porting the JXTA C implementation to the target robotic platform and potentially eliminating the TCP/IP layer, using UDP instead of TCP or using an adaptive TCP/IP stack. We also propose a future areas of investigation; how to seed the configuration for the Personal area network (PAN) Bluetooth protocol extension so a Bluetooth TCP/IP link is more quickly formed and using the STP to allow multi-hop messaging and transfer of skills.

Zugl.: Duisburg, Essen, Univ., Diss., 2005

Made available in DSpace on 2016-06-02T19:05:40Z (GMT). No. of bitstreams: 1 2682.pdf: 1041726 bytes, checksum: e49637dd5b33d0f2161039b6aea0e32e (MD5) Previous issue date: 2007-12-20 / Financiadora de Estudos e Projetos / Distributed and parallel simulations can be used to create virtual collaborative environments that involve human beings in applications of training, entertainment, etc. The High Level Architecture - HLA, developed by the Defense Modeling and Simulation Office (DMSO) of the North American Department of Defense - DoD and adopted by IEEE for modeling and simulation of high level, is a framework of simulation standardization that basically aims at the reuse and interoperability of/among simulations. The HLA comprises the following services: Federation Management, Declaration Management, Object Management, Ownership Management, Time Management and Distribution of Data Management (DDM). RTI (Run-Time Infrastructure) is the implementation of the interface specification of HLA, whose main objective is to separate the communication from the simulation. A version of the RTI (RTI kit version 1.3 from Georgia Institute of Technology - Georgia Tech) was installed in the cluster of the Computer Department of the Federal University of São Carlos. This version consists of a set of support libraries for real-time distributed simulation. The problem with this version of the RTI is that it has many limitations, such as lack of support for human interaction. In order to overcome these limitations, an architecture was developed and evaluated, as part of this work, that uses the JXTA platform to initiate federates (simulations) and federations (set of federates) at runtime web services. This architecture aims to manage the distribution of data among federates, one of the most important services for distributed simulations. / Simulações paralelas e distribuídas podem ser utilizadas para criar ambientes virtuais colaborativos que envolvem seres humanos em aplicações de treinamento, entretenimento, etc. A Arquitetura de Alto Nível (High Level Architecture - HLA) desenvolvida pelo Escritório de Modelagem e Simulação de Defesa (DMSO) do Departamento de Defesa Norte-Americano DoD e adotada pelo IEEE para modelagem e simulação de alto nível é um framework de padronização de simulações que visa, basicamente, o reuso e a interoperabilidade de/entre simulações. A HLA compreende os seguintes serviços: Gerenciamento de Federação (conjunto de federados), Gerenciamento de Declaração, Gerenciamento de Objetos, Gerenciamento de Posse, Gerenciamento de Tempo e Gerenciamento de Distribuição de Dados (DDM). A RTI (Run-Time Infrastructure) é a implementação da especificação de interface da HLA, cujo objetivo principal é separar a comunicação da simulação. Uma versão da RTI (kit RTI versão 1.3 do Instituto de Tecnologia da Georgia - Georgia Tech) foi instalada no cluster do DC da UFSCar. Esta versão consiste de um conjunto de bibliotecas de suporte a simulações de tempo-real distribuídas. O problema com esta versão da RTI é que ela possui várias limitações, dentre elas, a falta de suporte à interação. De modo a superar essas limitações uma arquitetura foi desenvolvida e avaliada, como parte deste trabalho, que utiliza a plataforma JXTA para iniciar federados (simulações) e federações (conjunto de federados) em tempo de execução por meio de serviços web. Esta arquitetura visa gerenciar a distribuição de dados entre os federados, um dos serviços mais importantes de simulações distribuídas.

Made available in DSpace on 2014-06-12T15:59:37Z (GMT). No. of bitstreams: 2 arquivo5349_1.pdf: 1338520 bytes, checksum: 967ea568492e0071544a3a6f547aed59 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / A TV Digital Interativa traz consigo uma série de mudanças que vai muito além da melhoria de qualidade em áudio e vídeo. Ela trará o aumento da diversidade e disponibilidade de conteúdo multimídia e fará com que as pessoas deixem de ser meros espectadores para se tornarem também usuários de aplicativos multimídia interativos. Estes aplicativos virão com o conteúdo multimídia e irão permitir que o usuário possa interagir ativamente com o conteúdo exibido ou até mesmo com as emissoras, pois os padrões de TV digital prevêem a existência de um canal de interação através do qual o aparelho de TV possa se comunicar numa rede de computadores, como a Internet, por exemplo. Desta forma, as aplicações de TV digital poderão acessar serviços como e-mail, Internet-banking e comércio eletrônico. No entanto, estes são serviços centralizados e não exploram a interatividade entre as pessoas. É fácil prever que, num futuro próximo, existirá demanda por aplicações que explorem a interatividade entre as pessoas. Porém, fazer com que estas aplicações se comuniquem é um verdadeiro desafio, pois o uso de servidores para intermediar mensagens está sujeito a problemas de escalabilidade, e a troca direta de mensagens é prejudicada pela heterogeneidade da rede em que o canal de interação é disponibilizado. Este trabalho propõe um Middleware para este tipo de aplicação distribuída. O Middleware proposto foi baseado no modelo de comunicação peer-to-peer, pois, após a análise dos requisitos deste tipo de software distribuído, verificou-se que este modelo é o que melhor se adequa. O mesmo foi construído sobre a plataforma JXTA, que resolve os problemas de infra-estrutura da rede, compreendendo um serviço avançado de busca e um mecanismo de invocação remota de método, semelhante à tecnologia Java RMI