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No. of bitstreams: 1 DissIMF.pdf: 12997797 bytes, checksum: 61ca28804fe846c5e4f1f3d97a366017 (MD5) Previous issue date: 2015-11-13 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / The popularization of mobile devices capable of communicating via wireless network technologies allows us to consider different scenarios in which these devices may autonomously interact with each other. The envisioned communications would occur in a P2P fashion, as each device could simultaneously provide and consume services. A mechanism for dynamically discovering nearby devices and the available services would be necessary. Although a few existing applications already provide the direct interaction among devices they are purpose-specific and rely on pre-configured information for identifying other devices. A service-oriented architecture (SOA), based on HTTP requests and the REST or SOAP protocols, is commonly used in this type of communication. However, automatically finding available known services is still challenging. Service discovery is usually based exclusively on service name, which is not very flexible. This work proposes a new model for the direct interaction between computing devices. In an attempt to facilitate service discovery and selection we propose a content centric model in which interactions are defined according to an object’s type and the action to be applied to it. The proposed approach can workatop of existing discovery protocols, based on extensible metadata fields and on existing service data. Our proposal is evaluated according to i) the viability of direct communication between nearby devices, even when carried by users or associated to vehicles; ii) the proposed service discovery and matching using the content centric approach; iii) the effectiveness of a middleware to support the development of generic applications for direct device communication. Simulation results show our proposed model is viable. A preliminary implementation of the middleware was also evaluated and the results show that spontaneous, opportunistic, service-based interactions among devices can be achieved for different types of services. / A popularização de dispositivos móveis dotados de capacidade de comunicação sem fio possibilita a criação de ambientes onde estes dispositivos interagem diretamente entre si. Essas comunicações ocorrem no modelo P2P, de forma que cada dispositivo pode implementar simultaneamente papéis de cliente e de servidor. Contudo, para que ocorram interações di- retas entre dispositivos através de aplicações, é preciso que estes dispositivos implementem algum mecanismo de descoberta. Atualmente, a maioria das aplicações que se comunicam diretamente utilizam informações pré-configuradas para identificação de dispositivos e serviços. Uma forma utilizada para interação entre dispositivos é através da oferta e consumo de serviços utilizando a arquitetura orientada a serviços (SOA), baseada em requisições HTTP utilizando os padrões REST ou SOAP. Um problema recorrente para consumidores de serviços é a identificação de serviços disponíveis. A identificação utilizada em protoco- los de descoberta existentes baseia-se apenas no nome do serviço, salvo em comunicações pré-configuradas, o que não apresenta flexibilidade para descobrir novos serviços. De forma a facilitar a troca de informações entre dispositivos, este trabalho propõe um modelo em que interações diretas entre dispositivos sejam centradas no conteúdo envolvido na interação e nas ações que se deseja realizar sobre eles. Para tanto, uma identificação de serviço pode ser baseada em metadados que são adicionados às descrições de serviços existentes, ou em informações obtidas com protocolos de descoberta de serviço existentes. Para avaliar o modelo proposto, esse trabalho apresenta um estudo sobre i) a viabilidade de interações diretas entre dispositivos, considerando suas mobilidades; ii) o uso de um modelo de interação centrado em conteúdo e ação; iii) o desenvolvimento de um Middleware para simplificar o desenvolvimento de aplicações que usem o modelo de serviço proposto. Os resultados de simulação obtidos mostram que o modelo é viável. Além disso, uma versão preliminar do Middleware proposto foi avaliada e mostra que a interação direta entre dispositivos pode ocorrer de forma oportunística e espontânea.

[pt] A popularização da Internet das Coisas (IoT, Internet of Things) provocou uma crescente oportunidade para a criação de aplicações em diversas áreas, através da combinação do uso de sensores e/ou atuadores. Em ambientes de IoT, o papel de elementos chamados de gateways consiste em fornecer uma camada de comunicação intermediária entre os dispositivos de IoT e serviços de nuvem. Um fator crucial para a construção de aplicações em larga escala é que os dispositivos de IoT possam ser utilizados de maneira transparente, num paradigma orientado a serviços, onde detalhes de comunicação e configuração destes objetos são tratados pelos gateways. No modelo de serviços, as aplicações devem descobrir as interfaces de alto-nível dos dispositivos e não precisam lidar com detalhes subjacentes, que são tratados pelos gateways. Em cenários de grande dinamismo e mobilidade (com conexões e desconexões de dispositivos acontecendo a todo momento), a descoberta e configuração de objetos deve ocorrer de forma contínua. Os protocolos de descoberta de serviços tradicional, como o Universal Plug and Play (UPnP) ou o Service Location Protocol (SLP), não foram desenvolvidos levando em consideração o alto dinamismo de ambientes IoT. Nesse sentido, introduzimos o processamento de eventos complexos (CEP), que é uma tecnologia para processamento em tempo real de fluxos de eventos heterogêneos, que permite a utilização de consultas em linguagem CQL (Continuous Query Language) para a busca de eventos de interesse. Em um modelo onde os eventos relacionados à descoberta de sensores são enviados para um fluxo CEP, consultas expressivas são escritas para que uma aplicação descubra continuamente serviços de interesse. Este trabalho apresenta a extensão do MHub/CDDL para o suporte à descoberta contínua de serviços em IoT, utilizando CEP. O MHub/CDDL (Mobile Hub / Context Data Distribution Layer) é um middleware para descoberta de serviços e gerenciamento de qualidade de contexto em IoT, desenvolvido numa parceria entre o Laboratory for Advanced Collaboration (LAC) da PUC-Rio e o Laboratório de Sistemas Distribuídos Inteligentes (LSDi) da Universidade Federal do Maranhão (UFMA). A implementação deste trabalho é feita para a plataforma Android (Java) e um estudo de caso no domínio de estacionamentos inteligentes é conduzido e implementado, elucidando o uso do mecanismo de descoberta contínuo. / [en] The popularization of the Internet of Things sparked a growing opportunity for the creation of applications in various areas, by combining the use of sensors and/or actuators. In IoT environments, the role of elements called gateways is to provide an intermediate communication layer between IoT devices and cloud services. A crucial factor for the construction of large-scale applications is to allow the use of IoT devices in a transparent manner, in a service-oriented paradigm, where details of communication and configuration are handled by the gateways. In service model, applications must discover the high-level interfaces of the devices and do not have to deal with underlying details that are handled by gateways. In scenarios of high dynamism and mobility (with connections and disconnections of devices occuring all the time), this discovery and configuration must occur continuously. Traditional service discovery protocols, such as Universal Plug and Play (UPnP) or Service Location Protocol (SLP), have not been developed taking into consideration the high dinamicity of IoT environments. In this sense, we introduce complex event processing (CEP), which is a technology for real-time processing of heterogeneous event flows, which allows the use of CQL (Continuous Query Language for the search of events of interest. In a model where events related to sensor discovery are sent to a CEP flow, expressive queries are written for an application to continuously discover services of interest. This work presents the extension of MHub / CDDL to support continuous service discovery in IoT, using CEP. The MHub / CDDL (Mobile Hub / Context Data Distribution Layer) is a middleware for service discovery and quality context management in IoT, developed in a partnership between the Laboratory for Advanced Collaboration (LAC) from PUC-Rio and the Laboratório de Sistemas Distribuídos Inteligentes (LSDi) from Universidade Federal do Maranhão (UFMA). The implementation of this work is done in Android (Java) platform and a case study in the domain of smart parking is conducted and implemented, elucidating the use of the continuous discovery mechanism.

Ces dernières années ont témoigné du succès du projet Linked Open Data (LOD) et de la croissance du nombre de sources de données sémantiques disponibles sur le web. Cependant, il y a encore beaucoup de données qui ne sont pas encore mises à disposition dans le LOD telles que les données sur demande, les données de capteurs etc. Elles sont néanmoins fournies par des API des services Web. L'intégration de ces données au LOD ou dans des applications de mashups apporterait une forte valeur ajoutée. Cependant, chercher de tels services avec les outils de découverte de services existants nécessite une connaissance préalable des répertoires de services ainsi que des ontologies utilisées pour les décrire.Dans cette thèse, nous proposons de nouvelles approches et des cadres logiciels pour la recherche de services web sémantiques avec une perspective d'intégration de données. Premièrement, nous introduisons LIDSEARCH, un cadre applicatif piloté par SPARQL pour chercher des données et des services web sémantiques.De plus, nous proposons une approche pour enrichir les descriptions sémantiques de services web en décrivant les relations ontologiques entre leurs entrées et leurs sorties afin de faciliter l'automatisation de la découverte et de la composition de services. Afin d'atteindre ce but, nous utilisons des techniques de traitement automatique de la langue et d'appariement de textes basées sur le deep-learning pour mieux comprendre les descriptions des services.Nous validons notre travail avec des preuves de concept et utilisons les services et les ontologies d'OWLS-TC pour évaluer nos approches proposées de sélection et d'enrichissement. / The last years witnessed the success of the Linked Open Data (LOD) project as well as a significantly growing amount of semantic data sources available on the web. However, there are still a lot of data not being published as fully materialized knowledge bases like as sensor data, dynamic data, data with limited access patterns, etc. Such data is in general available through web APIs or web services. Integrating such data to the LOD or in mashups would have a significant added value. However, discovering such services requires a lot of efforts from developers and a good knowledge of the existing service repositories that the current service discovery systems do not efficiently overcome.In this thesis, we propose novel approaches and frameworks to search for semantic web services from a data integration perspective. Firstly, we introduce LIDSEARCH, a SPARQL-driven framework to search for linked data and semantic web services. Moreover, we propose an approach to enrich semantic service descriptions with Input-Output relations from ontologies to facilitate the automation of service discovery and composition. To achieve such a purpose, we apply natural language processing techniques and deep-learning-based text similarity techniques to leverage I/O relations from text to ontologies.We validate our work with proof-of-concept frameworks and use OWLS-TC as a dataset for conducting our experiments on service search and enrichment.

In modern Mobile Ad hoc Networks (MANETs), service discovery is a major component for mobile devices to exchange data and find available services. However, service discovery architectures developed and adopted by the industry either are not appropriate for MANETs or cannot provide security and privacy protection to clients. Service discovery architectures could be either directory-based or directory-less. Both of the two types of architectures suffer from certain security or privacy issues: The directory-based architecture requires a directory server to facilitate communication between service providers and users, which makes the directory server a single point of failure and may harm users’ privacy if the directory server is honestbut- curious; the directory-less architecture solves these two problems but without a trusted directory, the Denial of Service (DoS) attacks can be easily performed on all entities in the system since the mutual authentication between entities consumes significant computational resource. Wi-Fi Aware, a recently introduced Wi-Fi-based connectivity, allows MANETs nodes to discover and connect directly to each other without any infrastructure. Moreover, the size of the message transmitted in this process is large enough (around 255 bytes) for security and privacy protection. So in this thesis, we implemented a Wi-Fi Aware-based decentralized secure service discovery system that allows the clients to directly discover nearby service providers and provide mutual authentication between them without a directory server. In our system we leverage several schemes, including bloom filter, Timed Efficient Stream Loss- Tolerant Authentication (TESLA), and client puzzle. A set of experiments are carried out for the evaluation of the implemented system. The evaluation results show that our system meets most of the security requirements of service discovery architectures with acceptable processing delays. / I moderna moblie ad hoc -nätverk (MANETs) är service discovery en huvudkomponent för noder för att utbyta data och hitta andras tjänster. Men serviceupptäcktsarkitekturerna som utvecklats och antagits av branschen är antingen inte lämpliga i MANET eller kan inte ge kunderna säkerhet och integritetsskydd. service discovery-arkitekturer är katalogbaserade eller kataloglösa. Båda de två arkitekturerna lider av vissa säkerhetseller sekretessproblem: Den katalogbaserade arkitekturen kräver att katalogservern underlättar kommunikationen mellan tjänsteleverantörer och användare, vilket gör katalogservern till en enda felpunkt och kan skada användarnas integritet om katalogservern är ärlig-men-nyfiken; Den kataloglösa arkitekturen löser dessa två problem men utan en pålitlig katalog kan Denial of Service (DoS) -attacker enkelt utföras på alla enheter i systemet eftersom den ömsesidiga autentiseringen mellan enheter förbrukar massor av beräkningsresurser. Nyligen, med den nyaWi-Fi-funktionen som kallas WiFi-Aware cite wifiaware, kan MANET-noder upptäcka och ansluta direkt till varandra utan någon annan typ av anslutning mellan dem . Dessutom är storleken på meddelandet som överförs i denna process tillräckligt stor (cirka 255 byte) för säkerhetsautentisering. Så i denna avhandling implementerade vi ett Wi-Fi Aware-baserat Decentralized Secure service discovery-system som gör att klienterna direkt kan upptäcka närliggande tjänsteleverantörer och tillhandahålla ömsesidig autentisering mellan dem utan en katalogserver. I vårt system används flera system för att skydda vårt system från ovanstående säkerhets- och integritetsfrågor, bland annat blomfilter, Timed Efficient Stream Loss-Tolerant Authentication (TESLA) och klientpussel. En uppsättning utvärderingsförsök utförs för det implementerade systemet. Utvärderingsresultaten visar att vårt system uppfyller de flesta säkerhetskraven för service discovery -arkitekturer med en acceptabel bearbetningsfördröjning.

With the development of 5G technology and edge computing, more and more network application services have been migrated to the cloud network in order to improve the performance, availability and ensure Quality of Service. Edge computing has essentially changed the service deployment model and reduce the latency further for better customer experience, which is realized by deploying network service replicas in geographically distributed edge sites. However, how to discover edge application servers and select a proper instance to serve the edge users becomes an important research topic. This master thesis project addresses the problem by leveraging DNS based service selection mechanism, designing and implementing stable match based service selection algorithms with the aim of minimizing latency between edge users and services and balance the load among edge sites, and integrating the solutions by RESTful APIs. To evaluate the performance of the service selection algorithms, a set of experiments are carried on different simulated topologies with different traffic pattern. The experimental results show that the stable match algorithm and its variants can significantly reduce the average latency by up to 50% compared to traditional approaches, while the enhanced stable match based algorithms are able to have the same load balancing effect with the widely used Round Robin algorithm. / Med utvecklingen av 5G-teknik och edge computing har fler nätverkstjänster migrerats till molnätet för att förbättra prestanda, tillgänglighet och säkerställa servicekvalitet. Edge computing har i huvudsak förändrat tjänster distribution modellen och minskat latensen ytterligare för bättre kundupplevelse, vilket realiseras genom att distribuera nätverkstjänstreplikat på geografiskt distribuerade kantsajter. Hur man upptäcker kantappservrar och väljer en rätt instans för att betjäna kantanvändarna blir dock ett viktigt forskningsämne. Detta projekt löser problemet genom att utnyttja DNS-baserad mekanism för tjänstval, designa och implementera stabila matchbaserade algoritmer för tjänsteval i syfte att minimera latens mellan kantanvändare och tjänster och balansera belastningen mellan kantsajter och integrera lösningarna med RESTful API:er. För att utvärdera prestandan för algoritmerna för val av tjänster utförs en uppsättning experiment på olika simulerade topologier med olika trafikmönster. De experimentella resultaten visar att den stabila matchningsalgoritmen och dess varianter avsevärt kan minska den genomsnittliga latensen med upp till 50% jämfört med traditionella metoder, medan de förbättrade stabila matchbaserade algoritmerna kan ha samma belastningsbalanseringseffekt med den mycket använda Round Robin algoritm.

According to the service orientation design paradigm there are business (BS) and electronic services (ES). BS encapsulate business concerns. ES encapsulate computing systems, information systems and software applications. In environments with a high number of BS and ES the decision on which ES provides the most suitable support for a certain BS is not a trivial task. The objective of the thesis is to provide models, methods, and techniques for preselection of ES for a given BS. Preselection is about reducing the large amount of ES to a significant smaller amount under the consideration of a particular BS.

According to the service orientation design paradigm there are business (BS) and electronic services (ES). BS encapsulate business concerns. ES encapsulate computing systems, information systems and software applications. In environments with a high number of BS and ES the decision on which ES provides the most suitable support for a certain BS is not a trivial task. The objective of the thesis is to provide models, methods, and techniques for preselection of ES for a given BS. Preselection is about reducing the large amount of ES to a significant smaller amount under the consideration of a particular BS.

Les sources de données multimédias provenant de divers domaines (médical, tourisme, commerce, art et culture, etc.) sont devenues incontournables sur le web. L’accès à ces sources multimédias dans les systèmes distribués pose de nouveaux problèmes en raison de nombreux paramètres : volumétrie, diversité des interfaces, format de représentation, localisation, etc. En outre, l’exigence de plus en plus forte des utilisateurs et des applications à vouloir intégrer la sémantique dans la recherche d’information pose de nouvelles questions à résoudre. Pour prendre en compte cette nouvelle complexité, nous nous intéressons dans notre travail de recherche aux solutions d’intégration de données basées sur les services web. Dans cette thèse, nous proposons une approche orientée service pour la recherche sémantique de contenus multimédia. Nous avons appelé cette approche SeSaM (Semantic Search of Multimedia content). SeSaM repose sur la définition d’un nouveau type de services accédant aux contenus multimédias, qui est les services MaaS (Multimedia as a Services). Elle est basée sur un processus en deux phases : description et découverte des services MaaS. En ce qui concerne la description de services MaaS, nous avons défini le langage SA4MaaS (Semantic Annotation for MaaS services), qui est une extension de SAWSDL (recommandation W3C). L’idée principale de ce langage est l’intégration, en plus de la sémantique métier, de la sémantique de l’information multimédia dans la description des services MaaS. En ce qui concerne la découverte de services MaaS, nous avons proposé un nouveau matchmaker MaaS-MX (MaaS services Matchmaker) adapté au modèle de description des MaaS. MaaS-MX est composé de deux étapes primordiales : appariement métier et appariement multimédia. L’appariement métier consiste à comparer la description métier des services et de la requête, tandis que l’appariement multimédia compare la description multimédia des services et de la requête. L’approche a été prototypée et évaluée dans deux domaines différents : médical et tourisme. Les résultats indiquent que l’utilisation de l’appariement métier et l’appariement multimédia a considérablement amélioré les performances des systèmes de recherche de données multimédias. / Multimedia data sources from various fields (medical, tourism, trade, art and culture, etc.) became essential on the web. Accessing to multimedia data in distributed systems poses new challenges due to many system parameters: volume, diversity of interfaces, representation format, location, etc. In addition, the growing needs of users and applications to incorporate semantics in the information retrieval pose new issues. To take into account this new complexity, we are interested in our research of data integration solutions based on web services. In this thesis, we propose an approach-oriented service for the semantic search of multimedia content. We called this approach SeSaM (Semantic Search of Multimedia content). SeSaM is based on the definition of a new pattern of services to access multimedia content, which is the MaaS services (Multimedia as a Services). It is based on a two-phase process: description and discovery of MaaS services. As for the MaaS services description, we have defined the SA4MaaS language (Semantic Annotation for MaaS services), which is an extension of SAWSDL (W3C recommendation). The main idea of this language is the integration, in addition to business domain semantic, of multimedia information semantics in the MaaS services description. As for the MaaS service discovery, we have proposed a new matchmaker MaaS-MX (MaaS services Matchmaker) adapted to the MaaS services description model. MaaS-MX is composed of two essential steps: domain matching and multimedia matching. Domain matching consists in comparing the business domain description of MaaS services and the query, whereas multimedia matching compares the multimedia description of MaaS services and the query. The approach has been implemented and evaluated in two different domains: medical and tourism. The results indicate that using both domain and multimedia matching considerably improves the performance of multimedia data retrieving systems.

Lors de la dernière décennie, le nombre d'appareils possédant des capacités sans fil a très fortement augmenté, attirant ainsi le grand public vers les réseaux mobiles sans fil. Nous considérons le cas des réseaux mobiles ad hoc aussi connu sous le nom de MANET (Mobile Ad hoc NETworks). La caractéristique principale des MANETs est la grande dynamicité des noeuds (induite pas le mouvement des utilisateurs), la propriété volatile des transmissions sans fil, le comportement des utilisateurs, les services et leurs utilisations. Cette thèse propose une solution complète pour la découverte de service dans les réseaux ad hoc, de la couche réseau sous-jacente à la découverte de service à proprement dite. La première contribution est le protocole Stable Linked Structure Flooding (SLSF) qui établi une structure basée sur des clusters stable et permet d'obtenir une dissémination efficace qui passe à l'échelle. La seconde contribution est SLSR (Stable Linked Structure Routing) qui utilise la structure de dissémination de SLSF et permet de faire du routage à travers le réseau. En utilisant ces protocoles comme base, nous proposons d'améliorer la découverte de service en prenant en compte le contexte. De plus, nous avons contribué à la simulation réseau en couplant des modèles et des simulateurs de domaines différents qui une fois couplés permettent d'élaborer et la simuler des scénarios riches et variés adaptés aux MANETs. Cette thèse à été réalisé au sein du projet ANR SARAH qui avait pour but le déploiement de service multimédia dans une architecture ad hoc hybride / In the last decade, the number of wireless capable devices increased drastically along with their popularity. Devices also became more powerful and affordable, attracting more users to mobile networks. In this thesis we consider service discovery in Mobile Ad hoc NETworks, also called MANETs, that are a collection of devices that communicate with each other spontaneously whenever they are in wireless transmission range without any preexisting infrastructure. The main characteristic of MANETs is the high dynamic of nodes (induced by the users moving around), the volatile wireless transmissions, the user behavior, the services and their usage. This thesis proposes a complete solution for service discovery in ad hoc networks, from the underlying network up to the service discovery itself. A first contribution is the Stable Linked Structure Flooding (SLSF) protocol that creates stable based cluster structure and thereby provides scalable and efficient message dissemination. The second contribution is the Stable Linked Structure Routing (SLSR) protocol that uses the SLSF dissemination structure to enable routing capabilities. Using those protocols as basis, we propose to improve service discovery by additionally considering context awareness and adaptation. Moreover, we also contributed on improving simulations by coupling simulators and models that, together, can model and simulate the variety and richness of ad hoc related usage scenarios and their human characteristic

nombre croissant de dispositifs informatiques par le biais de technologies réseaux sans fil basées ou non sur des infrastructures (WLAN, Bluetooth, GSM, GPRS, UMTS). Une des problématiques majeures de l'informatique diffuse est de faire communiquer de façon dynamique, spontanée et transparente ces différents dispositifs entre eux indépendamment de leurs hétérogénéités matérielle et logicielle. Les intergiciels ont été introduits dans cet objectif, cependant étant donné leur diversité, une nouvelle source d'hétérogénéité de plus haut niveau apparaît, notamment au niveau de leur protocole d'interaction. Actuellement, deux méthodes permettent de résoudre ces incompatibilités : la substitution et la traduction de protocoles. La première requiert la conception de nouveaux intergiciels capables de s'adapter en fonction de leur environnement d'exécution afin de résoudre dynamiquement l'hétérogénéité des intergiciels existants. L'avantage de cette méthode est de fournir une interopérabilité dynamique. En revanche, son inconvénient est d'être non transparente : elle crée une nouvelle source d'hétérogénéité entre ces nouveaux intergiciels, et nécessite de développer des applications qui leur sont spécifiques. La seconde méthode, quant à elle, est transparente : elle ne requiert ni la conception de nouveaux intergiciels, ni le développement de nouvelles applications. Cependant, elle reste statique et planifiée contrairement à la précédente méthode. Dans le contexte de l'informatique diffuse, ces deux méthodes sont complémentaires. Notre contribution consiste à combiner ces deux approches. A l'aide des langages de processus, nous proposons, dans un premier temps, une spécification formelle de notre solution qui permet de résoudre l'hétérogénéité des intergiciels quels que soient la spécificité de leurs caractéristiques, de leurs protocoles et de leurs technologies. Dans un second temps, nous présentons deux systèmes, basés sur cette spécification, conçus pour résoudre : (i) les incompatibilités des protocoles de découverte de services, (ii) les incompatibilités des protocoles de communication. Leur particularité est d'assurer une interopérabilité dynamique et transparente sans requérir de modifications des applications et des intergiciels existants. A partir de nos différentes expérimentations, il apparaît que le surcoût de cette solution pour résoudre les incompatibilités de protocoles est raisonnable.