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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Opportunistic Overlays: Efficient Content Delivery in Mobile Environments

Chen, Yuan 13 April 2005 (has links)
Middleware has become a key enabler for the development of distributed applications. Unfortunately, conventional middleware technologies do not yet offer sufficient functionality to make them suitable for mobile environments. This dissertation proposes a novel middleware approach termed opportunistic overlays and its dynamically reconfigurable support framework for building efficient mobile applications. Specifically, we address the inefficiency of content delivery introduced by node mobility and by dynamically changing system loads, in the context of publish/subscribe systems. In response to changes in physical network topology, in nodes' physical locations, and in network node behaviors, the opportunistic overlay approach dynamically adapts event dissemination structures (i.e., broker overlays) with the goal of optimizing end-to-end delays in event delivery. Adaptation techniques include the dynamic construction of broker overlay networks, runtime changes of mobile clients' assignments to brokers, and dynamic broker load balancing. Essentially, opportunistic overlays implement a middleware-level analogue of the networking routing protocols used in wireless communications (i.e., Mobile IP, AODV, DSR and DSDV). By thus coordinating network- with middleware-level routing, opportunistic overlays can attain substantial performance improvements over non-adaptive event systems. Such improvements are due to their use of shorter network paths and better balancing of loads across event brokers. Opportunistic overlays and the adaptive methods they use are realized by a set of distributed protocols implemented in a Java-based publish/subscribe infrastructure. Comprehensive performance evaluations are performed via simulation, emulation, and with two representative applications on actual networks. Experimental results demonstrate that the opportunistic overlay approach is practically applicable and that the performance advantages attained from the use of opportunistic overlays can be substantial, in both infrastructure-based mobile environments and mobile ad hoc networks.
2

An adaptive middleware for mobile information systems

Gruhn, Volker, Hülder, Malte 28 January 2019 (has links)
The advances in mobile telecommunication networks as well as in mobile device technology have stimulated the development of a wide range of mobile applications. While it is sensible to install at least some components of applications on mobile devices to gain independence of rather unreliable mobile network connections, it is difficult to decide about the suitable application components and the amount of data to be provided. Because the environment of a mobile device can change and mobile business processes evolve over time, the mobile system should adapt to these changes dynamically to ensure productivity. In this paper, we present a mobile middleware that targets typical problems of mobile applications and dynamically adapts to context changes at runtime by utilizing reconfiguration triggers.
3

High-performance near-time processing of bulk data

Swientek, Martin January 2015 (has links)
Enterprise Systems like customer-billing systems or financial transaction systems are required to process large volumes of data in a fixed period of time. Those systems are increasingly required to also provide near-time processing of data to support new service offerings. Common systems for data processing are either optimized for high maximum throughput or low latency. This thesis proposes the concept for an adaptive middleware, which is a new approach for designing systems for bulk data processing. The adaptive middleware is able to adapt its processing type fluently between batch processing and single-event processing. By using message aggregation, message routing and a closed feedback-loop to adjust the data granularity at runtime, the system is able to minimize the end-to-end latency for different load scenarios. The relationship of end-to-end latency and throughput of batch and message-based systems is formally analyzed and a performance evaluation of both processing types has been conducted. Additionally, the impact of message aggregation on throughput and latency is investigated. The proposed middleware concept has been implemented with a research prototype and has been evaluated. The results of the evaluation show that the concept is viable and is able to optimize the end-to-end latency of a system. The design, implementation and operation of an adaptive system for bulk data processing differs from common approaches to implement enterprise systems. A conceptual framework has been development to guide the development process of how to build an adaptive software for bulk data processing. It defines the needed roles and their skills, the necessary tasks and their relationship, artifacts that are created and required by different tasks, the tools that are needed to process the tasks and the processes, which describe the order of tasks.
4

AdaptiveRME e aspectCompose: um middleware adaptativo e um processo de composição orientado a aspecto para o desenvolvimento de software móvel e ubíquo / AdaptiveRME and aspectCompose: A middleware adaptative and a guided process of composition the aspects for the development of software móvel and ubiquitous

Rocha, Lincoln Souza January 2007 (has links)
ROCHA, Lincoln Souza. AdaptiveRME e aspectCompose: um middleware adaptativo e um processo de composição orientado a aspecto para o desenvolvimento de software móvel e ubíquo. 2007. 102 f. Dissertação (Mestrado em ciência da computação)- Universidade Federal do Ceará, Fortaleza-CE, 2007. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-11T18:16:05Z No. of bitstreams: 1 2007_dis_lsrocha.pdf: 2405680 bytes, checksum: 7063a81265f0d1a3757c5dff48a28581 (MD5) / Approved for entry into archive by Rocilda Sales (rocilda@ufc.br) on 2016-07-18T16:10:13Z (GMT) No. of bitstreams: 1 2007_dis_lsrocha.pdf: 2405680 bytes, checksum: 7063a81265f0d1a3757c5dff48a28581 (MD5) / Made available in DSpace on 2016-07-18T16:10:13Z (GMT). No. of bitstreams: 1 2007_dis_lsrocha.pdf: 2405680 bytes, checksum: 7063a81265f0d1a3757c5dff48a28581 (MD5) Previous issue date: 2007 / Ubiquitous computing is an extensive computational paradigm, which can provide solutions to regular citizens or can be useful to handle complex medical environment data, for example. This paradigm proposes a new human-computer interaction approach based on the proactivity of computers that makes users’ life easier. However, this approach demands a high level of collaboration and communication among the computational elements that compose the mobile and ubiquitous environments. One of the main challenges is related to the way of conceiving software systems capable of dealing with the high variation of resources and services, along with guaranteeing the interoperability among the diversity of computational elements that compose these environments. Therefore, this work proposes an adaptive middleware for móbile and ubiquitous environments that intends to solve heterogeneity and dynamicity problems. This dissertation also proposes a software composition process to reduce coupling between the proposed middleware and applications. The middleware uses dynamic adaptation and support for context-aware software development mechanisms, and the composition process uses Aspect-Oriented Programming (AOP) techniques. A case study is developed to evaluate the adaptive middleware’s functionalities and demonstrate the composing process. Furthermore, a performance analysis is presented to measure the proposed middleware’s impact in a wireless network. / A computação ubíqua é um paradigma computacional de grande abrangência, com aplicabilidades tanto para o cotidiano de um cidadão comum quanto para o tratamento de informações complexas em ambientes hospitalares. Este paradigma propõe uma nova forma de interação homem-computador baseada na proatividade dos computadores para facilitar a vida dos usuários. Entretanto, tal forma de interação demanda um alto grau de colaboração e comunicação entre os elementos computacionais que compõem os ambientes móveis e ubíquos. Um dos principais desafios está relacionado a maneira de como conceber sistemas de software capazes de lidar com a alta variação de recursos e serviços, além de garantir a interoperabilidade entre os diversos elementos computacionais que compõem estes ambientes. Este trabalho propõe, então, um middleware adaptativo para ambientes móveis e ubíquos com o objetivo de solucionar problemas de heterogeneidade e dinamicidade. Para diminuir o acoplamento entre o middleware proposto e as aplicações que o utilizam, esta dissertação também propõe um processo de composição de software. O middleware utiliza mecanismos de adaptação dinâmica e suporte ao desenvolvimento de software sensível ao contexto, e o processo de composição faz uso de técnicas de Programação Orientada a Aspectos (POA). Um estudo de caso é desenvolvido para avaliar a funcionalidade do middleware adaptativo e demonstrar a utilização do processo de composição. Além disso, uma análise de desempenho é apresentada para medir o impacto provocado pelo uso do middleware proposto em um ambiente de rede sem fio.
5

Um framework para configuração e gerenciamento de recursos e componentes em sistemas multimidia distribuidos abertos / A framework for configuration and management of resources and components in open distributed multimedia systems

Lopes, Adilson Barboza 30 August 2006 (has links)
Orientador: Mauricio Ferreira Magalhães / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-07T23:55:06Z (GMT). No. of bitstreams: 1 Lopes_AdilsonBarboza_D.pdf: 2506368 bytes, checksum: 78d6ece504fc0a9dcfd053303ba3b85b (MD5) Previous issue date: 2006 / Resumo: Em sistemas multimídia distribuídos existe uma diversidade de dispositivos de hardware, sistemas operacionais e tecnologias de comunicação. Para tratar os requisitos destas aplicações, os componentes do sistema precisam interagir entre eles considerando os aspectos de QoS de cada um dos elementos envolvidos. Neste contexto, esta tese apresenta o Cosmos ? um framework baseado em componentes proposto para dar suporte à configuração e gerenciamento de recursos em sistemas multimídia. Como prova de conceito do Cosmos, o framework definido foi usado no projeto do middleware AdapTV ? um middleware para sistemas de televisão digital interativa. O projeto do AdapTV explora os principais componentes dos modelos que foram definidos no Cosmos: o modelo de descrição de aplicações de forma independente de linguagens; o modelo de interconexão, que trata as questões de comunicação entre componentes heterogêneos usando diferentes tecnologias de comunicação; e o modelo de gerenciamento de QoS, que permite o monitoramento e a adaptação do sistema. Estes modelos foram explorados na implementação de um protótipo do middleware AdapTV e de uma aplicação distribuída que realiza a captura, transmissão e apresentação de um fluxo de vídeo. Para dar suporte à reusabilidade, o modelo explora o conceito de propriedades para estabelecer acordos de configuração (estáticos e dinâmicos) envolvendo negociações entre os requisitos dos componentes e as características da plataforma / Abstract: Distributed multimedia applications involve a diversity of hardware devices, operating systems and communication technologies. In order to fulfill the requirements of such applications, their constituting components need to interact with each other, as well as to consider QoS issues related to devices and transmission media. In such a context, this thesis presents the Cosmos component-based framework for configuration and management of resources of open, distributed multimedia systems. As a proof of concept, the framework was used in the design of the AdapTV middleware ? a middleware for interactive television which explores the major components of the Cosmos, including: the model to describe and represent applications independently of language aspects; the interconnection model that allows communication between components in heterogeneous and distributed multimedia environments; and the QoS management model that provides support for adaptation in the middleware player, triggered by QoS and user requirements changes. These models have been explored in the implementation of a prototype, which includes the AdapTV middleware and a distributed application example that captures, transmits and presents a video flow. In order to provide a generic and reusable approach, and to establish configuration agreements among component requirements and platform features, the framework explores the concept of properties / Doutorado / Engenharia de Computação / Doutor em Engenharia Elétrica
6

AdaptiveRME e aspectCompose: um middleware adaptativo e um processo de composiÃÃo orientado a aspecto para o desenvolvimento de software mÃvel e ubÃquo. / AdaptiveRME and aspectCompose: A middleware adaptative and a guided process of composition the aspects for the development of software mÃvel and ubiquitous

Lincoln Souza Rocha 03 August 2007 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A computaÃÃo ubÃqua à um paradigma computacional de grande abrangÃncia, com aplicabilidades tanto para o cotidiano de um cidadÃo comum quanto para o tratamento de informaÃÃes complexas em ambientes hospitalares. Este paradigma propÃe uma nova forma de interaÃÃo homem-computador baseada na proatividade dos computadores para facilitar a vida dos usuÃrios. Entretanto, tal forma de interaÃÃo demanda um alto grau de colaboraÃÃo e comunicaÃÃo entre os elementos computacionais que compÃem os ambientes mÃveis e ubÃquos. Um dos principais desafios està relacionado a maneira de como conceber sistemas de software capazes de lidar com a alta variaÃÃo de recursos e serviÃos, alÃm de garantir a interoperabilidade entre os diversos elementos computacionais que compÃem estes ambientes. Este trabalho propÃe, entÃo, um middleware adaptativo para ambientes mÃveis e ubÃquos com o objetivo de solucionar problemas de heterogeneidade e dinamicidade. Para diminuir o acoplamento entre o middleware proposto e as aplicaÃÃes que o utilizam, esta dissertaÃÃo tambÃm propÃe um processo de composiÃÃo de software. O middleware utiliza mecanismos de adaptaÃÃo dinÃmica e suporte ao desenvolvimento de software sensÃvel ao contexto, e o processo de composiÃÃo faz uso de tÃcnicas de ProgramaÃÃo Orientada a Aspectos (POA). Um estudo de caso à desenvolvido para avaliar a funcionalidade do middleware adaptativo e demonstrar a utilizaÃÃo do processo de composiÃÃo. AlÃm disso, uma anÃlise de desempenho à apresentada para medir o impacto provocado pelo uso do middleware proposto em um ambiente de rede sem fio. / Ubiquitous computing is an extensive computational paradigm, which can provide solutions to regular citizens or can be useful to handle complex medical environment data, for example. This paradigm proposes a new human-computer interaction approach based on the proactivity of computers that makes usersâ life easier. However, this approach demands a high level of collaboration and communication among the computational elements that compose the mobile and ubiquitous environments. One of the main challenges is related to the way of conceiving software systems capable of dealing with the high variation of resources and services, along with guaranteeing the interoperability among the diversity of computational elements that compose these environments. Therefore, this work proposes an adaptive middleware for mÃbile and ubiquitous environments that intends to solve heterogeneity and dynamicity problems. This dissertation also proposes a software composition process to reduce coupling between the proposed middleware and applications. The middleware uses dynamic adaptation and support for context-aware software development mechanisms, and the composition process uses Aspect-Oriented Programming (AOP) techniques. A case study is developed to evaluate the adaptive middlewareâs functionalities and demonstrate the composing process. Furthermore, a performance analysis is presented to measure the proposed middlewareâs impact in a wireless network.
7

Adaptive Middleware for Self-Configurable Embedded Real-Time Systems : Experiences from the DySCAS Project and Remaining Challenges

Persson, Magnus January 2009 (has links)
Development of software for embedded real-time systems poses severalchallenges. Hard and soft constraints on timing, and usually considerableresource limitations, put important constraints on the development. Thetraditional way of coping with these issues is to produce a fully static design,i.e. one that is fully fixed already during design time.Current trends in the area of embedded systems, including the emergingopenness in these types of systems, are providing new challenges for theirdesigners – e.g. integration of new software during runtime, software upgradeor run-time adaptation of application behavior to facilitate better performancecombined with more ecient resource usage. One way to reach these goals is tobuild self-configurable systems, i.e. systems that can resolve such issues withouthuman intervention. Such mechanisms may be used to promote increasedsystem openness.This thesis covers some of the challenges involved in that development.An overview of the current situation is given, with a extensive review ofdi erent concepts that are applicable to the problem, including adaptivitymechanisms (incluing QoS and load balancing), middleware and relevantdesign approaches (component-based, model-based and architectural design).A middleware is a software layer that can be used in distributed systems,with the purpose of abstracting away distribution, and possibly other aspects,for the application developers. The DySCAS project had as a major goaldevelopment of middleware for self-configurable systems in the automotivesector. Such development is complicated by the special requirements thatapply to these platforms.Work on the implementation of an adaptive middleware, DyLite, providingself-configurability to small-scale microcontrollers, is described andcovered in detail. DyLite is a partial implementation of the concepts developedin DySCAS.Another area given significant focus is formal modeling of QoS andresource management. Currently, applications in these types of systems arenot given a fully formal definition, at least not one also covering real-timeaspects. Using formal modeling would extend the possibilities for verificationof not only system functionality, but also of resource usage, timing and otherextra-functional requirements. This thesis includes a proposal of a formalismto be used for these purposes.Several challenges in providing methodology and tools that are usablein a production development still remain. Several key issues in this areaare described, e.g. version/configuration management, access control, andintegration between di erent tools, together with proposals for future workin the other areas covered by the thesis. / Utveckling av mjukvara för inbyggda realtidssystem innebär flera utmaningar.Hårda och mjuka tidskrav, och vanligtvis betydande resursbegränsningar,innebär viktiga inskränkningar på utvecklingen. Det traditionellasättet att hantera dessa utmaningar är att skapa en helt statisk design, d.v.s.en som är helt fix efter utvecklingsskedet.Dagens trender i området inbyggda system, inräknat trenden mot systemöppenhet,skapar nya utmaningar för systemens konstruktörer – exempelvisintegration av ny mjukvara under körskedet, uppgradering av mjukvaraeller anpassning av applikationsbeteende under körskedet för att nå bättreprestanda kombinerat med e ektivare resursutnyttjande. Ett sätt att nå dessamål är att bygga självkonfigurerande system, d.v.s. system som kan lösa sådanautmaningar utan mänsklig inblandning. Sådana mekanismer kan användas föratt öka systemens öppenhet.Denna avhandling täcker några av utmaningarna i denna utveckling. Enöversikt av den nuvarande situationen ges, med en omfattande genomgångav olika koncept som är relevanta för problemet, inklusive anpassningsmekanismer(inklusive QoS och lastbalansering), mellanprogramvara och relevantadesignansatser (komponentbaserad, modellbaserad och arkitekturell design).En mellanprogramvara är ett mjukvarulager som kan användas i distribueradesystem, med syfte att abstrahera bort fördelning av en applikation överett nätverk, och möjligtvis även andra aspekter, för applikationsutvecklarna.DySCAS-projektet hade utveckling av mellanprogramvara för självkonfigurerbarasystem i bilbranschen som ett huvudmål. Sådan utveckling försvåras avde särskilda krav som ställs på dessa plattformarArbete på implementeringen av en adaptiv mellanprogramvara, DyLite,som tillhandahåller självkonfigurerbarhet till småskaliga mikrokontroller,beskrivs och täcks i detalj. DyLite är en delvis implementering av konceptensom utvecklats i DySCAS.Ett annat område som får särskild fokus är formell modellering av QoSoch resurshantering. Idag beskrivs applikationer i dessa områden inte heltformellt, i varje fall inte i den mån att realtidsaspekter täcks in. Att användaformell modellering skulle utöka möjligheterna för verifiering av inte barasystemfunktionalitet, men även resursutnyttjande, tidsaspekter och andraicke-funktionella krav. Denna avhandling innehåller ett förslag på en formalismsom kan användas för dessa syften.Det återstår många utmaningar innan metodik och verktyg som är användbarai en produktionsmiljö kan erbjudas. Många nyckelproblem i områdetbeskrivs, t.ex. versions- och konfigurationshantering, åtkomststyrning ochintegration av olika verktyg, tillsammans med förslag på framtida arbete iövriga områden som täcks av avhandlingen. / DySCAS
8

Adaptive Middleware for Self-Configurable Embedded Real-Time Systems : Experiences from the DySCAS Project and Remaining Challenges

Persson, Magnus January 2009 (has links)
<p>Development of software for embedded real-time systems poses severalchallenges. Hard and soft constraints on timing, and usually considerableresource limitations, put important constraints on the development. Thetraditional way of coping with these issues is to produce a fully static design,i.e. one that is fully fixed already during design time.Current trends in the area of embedded systems, including the emergingopenness in these types of systems, are providing new challenges for theirdesigners – e.g. integration of new software during runtime, software upgradeor run-time adaptation of application behavior to facilitate better performancecombined with more ecient resource usage. One way to reach these goals is tobuild self-configurable systems, i.e. systems that can resolve such issues withouthuman intervention. Such mechanisms may be used to promote increasedsystem openness.This thesis covers some of the challenges involved in that development.An overview of the current situation is given, with a extensive review ofdi erent concepts that are applicable to the problem, including adaptivitymechanisms (incluing QoS and load balancing), middleware and relevantdesign approaches (component-based, model-based and architectural design).A middleware is a software layer that can be used in distributed systems,with the purpose of abstracting away distribution, and possibly other aspects,for the application developers. The DySCAS project had as a major goaldevelopment of middleware for self-configurable systems in the automotivesector. Such development is complicated by the special requirements thatapply to these platforms.Work on the implementation of an adaptive middleware, DyLite, providingself-configurability to small-scale microcontrollers, is described andcovered in detail. DyLite is a partial implementation of the concepts developedin DySCAS.Another area given significant focus is formal modeling of QoS andresource management. Currently, applications in these types of systems arenot given a fully formal definition, at least not one also covering real-timeaspects. Using formal modeling would extend the possibilities for verificationof not only system functionality, but also of resource usage, timing and otherextra-functional requirements. This thesis includes a proposal of a formalismto be used for these purposes.Several challenges in providing methodology and tools that are usablein a production development still remain. Several key issues in this areaare described, e.g. version/configuration management, access control, andintegration between di erent tools, together with proposals for future workin the other areas covered by the thesis.</p> / <p>Utveckling av mjukvara för inbyggda realtidssystem innebär flera utmaningar.Hårda och mjuka tidskrav, och vanligtvis betydande resursbegränsningar,innebär viktiga inskränkningar på utvecklingen. Det traditionellasättet att hantera dessa utmaningar är att skapa en helt statisk design, d.v.s.en som är helt fix efter utvecklingsskedet.Dagens trender i området inbyggda system, inräknat trenden mot systemöppenhet,skapar nya utmaningar för systemens konstruktörer – exempelvisintegration av ny mjukvara under körskedet, uppgradering av mjukvaraeller anpassning av applikationsbeteende under körskedet för att nå bättreprestanda kombinerat med e ektivare resursutnyttjande. Ett sätt att nå dessamål är att bygga självkonfigurerande system, d.v.s. system som kan lösa sådanautmaningar utan mänsklig inblandning. Sådana mekanismer kan användas föratt öka systemens öppenhet.Denna avhandling täcker några av utmaningarna i denna utveckling. Enöversikt av den nuvarande situationen ges, med en omfattande genomgångav olika koncept som är relevanta för problemet, inklusive anpassningsmekanismer(inklusive QoS och lastbalansering), mellanprogramvara och relevantadesignansatser (komponentbaserad, modellbaserad och arkitekturell design).En mellanprogramvara är ett mjukvarulager som kan användas i distribueradesystem, med syfte att abstrahera bort fördelning av en applikation överett nätverk, och möjligtvis även andra aspekter, för applikationsutvecklarna.DySCAS-projektet hade utveckling av mellanprogramvara för självkonfigurerbarasystem i bilbranschen som ett huvudmål. Sådan utveckling försvåras avde särskilda krav som ställs på dessa plattformarArbete på implementeringen av en adaptiv mellanprogramvara, DyLite,som tillhandahåller självkonfigurerbarhet till småskaliga mikrokontroller,beskrivs och täcks i detalj. DyLite är en delvis implementering av konceptensom utvecklats i DySCAS.Ett annat område som får särskild fokus är formell modellering av QoSoch resurshantering. Idag beskrivs applikationer i dessa områden inte heltformellt, i varje fall inte i den mån att realtidsaspekter täcks in. Att användaformell modellering skulle utöka möjligheterna för verifiering av inte barasystemfunktionalitet, men även resursutnyttjande, tidsaspekter och andraicke-funktionella krav. Denna avhandling innehåller ett förslag på en formalismsom kan användas för dessa syften.Det återstår många utmaningar innan metodik och verktyg som är användbarai en produktionsmiljö kan erbjudas. Många nyckelproblem i områdetbeskrivs, t.ex. versions- och konfigurationshantering, åtkomststyrning ochintegration av olika verktyg, tillsammans med förslag på framtida arbete iövriga områden som täcks av avhandlingen.</p> / DySCAS
9

Uma abordagem dirigida por modelos para desenvolvimento de middlewares auto-adaptativos para transmiss?o de fluxo de dados baseado em restri??es de QoS / Uma abordagem dirigida por modelos para desenvolvimento de middlewares auto-adaptativos para transmiss?o de fluxo de dados baseado em restri??es de QoS

Silva, Andre Gustavo Pereira da 15 March 2010 (has links)
Made available in DSpace on 2014-12-17T15:47:52Z (GMT). No. of bitstreams: 1 AndreGPS_DISSERT.pdf: 1357503 bytes, checksum: e140d06d3ffeafa9c2f772fa5796fc4d (MD5) Previous issue date: 2010-03-15 / The use of middleware technology in various types of systems, in order to abstract low-level details related to the distribution of application logic, is increasingly common. Among several systems that can be benefited from using these components, we highlight the distributed systems, where it is necessary to allow communications between software components located on different physical machines. An important issue related to the communication between distributed components is the provision of mechanisms for managing the quality of service. This work presents a metamodel for modeling middlewares based on components in order to provide to an application the abstraction of a communication between components involved in a data stream, regardless their location. Another feature of the metamodel is the possibility of self-adaptation related to the communication mechanism, either by updating the values of its configuration parameters, or by its replacement by another mechanism, in case of the restrictions of quality of service specified are not being guaranteed. In this respect, it is planned the monitoring of the communication state (application of techniques like feedback control loop), analyzing performance metrics related. The paradigm of Model Driven Development was used to generate the implementation of a middleware that will serve as proof of concept of the metamodel, and the configuration and reconfiguration policies related to the dynamic adaptation processes. In this sense was defined the metamodel associated to the process of a communication configuration. The MDD application also corresponds to the definition of the following transformations: the architectural model of the middleware in Java code, and the configuration model to XML / A utiliza??o da tecnologia de middleware em diversos tipos de sistemas, com a finalidade de abstrair detalhes de baixo n?vel relacionados com a distribui??o da l?gica da aplica??o, ? cada vez mais frequente. Dentre diversos sistemas que podem ser beneficiados com a utiliza??o desses componentes, podemos destacar os sistemas distribu?dos, onde ? necess?rio viabilizar a comunica??o entre componentes de software localizados em diferentes m?quinas f?sicas. Uma importante quest?o relacionada ? comunica??o entre componentes distribu?dos ? o fornecimento de mecanismos para gerenciamento da qualidade de servi?o. Este trabalho apresenta um metamodelo para modelagem de middlewares baseados em componentes que prov?em ? aplica??o a abstra??o da comunica??o entre componentes envolvidos em um fluxo de dados, independente da sua localiza??o. Outra caracter?stica do metamodelo ? a possibilidade de auto-adapta??o relacionada ao mecanismo de comunica??o utilizado, seja atrav?s da atualiza??o dos valores dos seus par?metros de configura??o, ou atrav?s da sua substitui??o por outro mecanismo, caso as restri??es de qualidade de servi?o especificadas n?o estejam sendo garantidas. Nesse prop?sito, ? previsto o monitoramento do estado da comunica??o (aplica??es de t?cnicas do tipo feedback control loop), analisando-se m?tricas de desempenho relacionadas. O paradigma de Desenvolvimento Dirigido por Modelos foi utilizado para gerar a implementa??o de um middleware que servir? como prova de conceito do metamodelo, e as pol?ticas de configura??o e reconfigura??o relacionadas com o processo de adapta??o din?mica; neste sentido, foi definido o metamodelo associado ao processo de configura??o de uma comunica??o. A aplica??o da t?cnica de MDD corresponde ainda ? defini??o das seguintes transforma??es: do modelo arquitetural do middleware para c?digo em linguagem Java, e do modelo de configura??o para c?digo XML

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