Добірка наукової літератури з теми "Dynamic service-oriented architecture"

Service-oriented software systems are inherently complex and have to cope with an increasing number of exceptional conditions in order to meet the system’s dynamic requirements. This work proposes an architecture framework which has exception handling capability. This framework ensures the credibility of service-oriented software, during the architectural stage, by adding exception handling-related architecture elements and modeling exception handling process. It allows a clear separation of concerns between the business function and the exception handling unit, using reflection mechanism. It plays an important guiding role for achieving reliable service-oriented system.

Simulation of dynamic service-based software systems is important for studying services that may change their composition and thus interactions at run-time. An approach based on Service Oriented Architecture-compliant DEVS (SOAD) and Dynamic Structure DEVS (DSDEVS) modeling approaches is developed to support structural changes in service model composition. To achieve this goal, a broker–executive model is devised based on the broker model defined for SOAD and the executive model defined for DSDEVS. The capability to simulate dynamic services is incorporated to the DEVS-Suite simulator. To demonstrate modeling of dynamic service-based software systems, a real voice communication system and a model of this system have been developed. The importance of enabling simulation-based design for adaptable systems is briefly discussed.

A new class of information system architecture, decision-oriented service systems, is spreading more and more. Decision-oriented service systems provide services that support decisions in business processes and products based on the capabilities of cloud-computing environments. To pave the way for the creation of design methods of business processes and products based on decision-oriented service systems, this article introduces a capability-oriented approach. Starting from technological capabilities, more abstract operational and dynamic capabilities are created. The framework created is based on an integrated conceptualization of decision-oriented service systems that allows capturing synergetic effects. By creating the framework, the gap between the technological capabilities of technologies and the strategic goals of enterprises shall be narrowed.

The research identifies the gap that there is a convergence of interoperability of Cloud Computing (CC), Service Oriented Architecture (SOA) and Enterprise Architecture (EA). Furthermore, it outlines the existing non dynamic links between EA and SOA that are currently practiced in the industry and confirmed by scholarly articles; and provides a state of art of the link that could exist in practice between cloud computing and SOA as researched from the published scholarly material. This researched paper also refers to the planned research to test this theory first by developing a logical architectural model of such a feasibility followed by a Proof of Concept

An important feature in collaborative environment is coordination, defined as the act of managing interdependencies between activities performed to achieve a goal. These interdependencies can be the result of loosely integrated collaborative activities (the use of coordination processes within the collaboration activities is not required) or tightly integrated collaborative activities (sophisticated coordination mechanisms are necessary). The existence of both activities along with the dynamic nature of these environments adds a greater complexity to the coordination that has not been taken into account in traditional collaborative systems. In this work, the authors present a partially Services Oriented Architecture (SOA) that defines and maintains dynamic coordination polities in collaborative systems based on coordination models.

The service-oriented architecture supports the dynamic assembly and runtime reconfiguration of complex open IT landscapes by means of runtime binding of service contracts, launching of new components and termination of outdated ones. Furthermore, the evolution of these IT landscapes is not restricted to exchanging components with other ones using the same service contracts, as new services contracts can be added as well. However, current approaches for modeling and verification of service-oriented architectures do not support these important capabilities to their full extend.In this report we present an extension of the current OMG proposal for service modeling with UML - SoaML - which overcomes these limitations. It permits modeling services and their service contracts at different levels of abstraction, provides a formal semantics for all modeling concepts, and enables verifying critical properties. Our compositional and incremental verification approach allows for complex properties including communication parameters and time and covers besides the dynamic binding of service contracts and the replacement of components also the evolution of the systems by means of new service contracts. The modeling as well as verification capabilities of the presented approach are demonstrated by means of a supply chain example and the verification results of a first prototype are shown.
Service-Orientierte Architekturen erlauben die dynamische Zusammensetzung und Rekonfiguration komplexer, offener IT Landschaften durch Bindung von Service Contracts zur Laufzeit, starten neuer Komponenten und beenden von veralteten. Die Evolution dieser Systeme ist nicht auf den Austausch von Komponenten-Implementierungen bei Beibehaltung der Service-Contracts beschränkt, sondern das Hinzufügen neuer Service-Contracts wird ebenfalls unterstützt. Aktuelle Ansätze zur Modellierung und Verifikation Service-Orientierter Architekturen unterstützen diese wichtigen Eigenschaften, wenn überhaupt, nur unvollständig. In diesem Bericht stellen wir eine Erweiterung des aktuellen OMG Vorschlags zur Service Modellierung mit UML - SoaML - vor, die diese Einschränkungen aufhebt. Unser Ansatz erlaubt die Modellierung von Service Contracts auf verschiedenen Abstraktionsniveaus, besitzt eine fundierte formale Semantik für alle eingeführten Modellierungskonzepte und erlaubt die Verifikation kritischer Eigenschaften. Unser kompositionaler und inkrementeller Verifikationsansatz erlaubt die Verifikation komplexer Eigenschaften einschließlich Kommunikationsparameter und Zeit und deckt neben der dynamischen Bindung von Service Contracts sowie dem Austausch von Komponenten auch die Evolution des gesamten Systems durch das Hinzufügen neuer Service Contracts ab. Die Modellierungs- als auch die Verifikationsfähigkeiten unseres vorgestellten Ansatzes werden durch ein Anwendungsbeispiel aus dem Bereich des Lieferkettenmanagements veranschaulicht.

Today’s market competitiveness and globalisation are putting pressure on organisations to join their efforts, to focus more on cooperation and interaction and to add value to their businesses. That is, most information systems supporting these cross-organisations are characterised as service-oriented business applications, where all the emphasis is put on inter-service interactions rather than intra-service computations. Unfortunately for the development of such inter-organisational service-oriented business systems, current service technology proposes only ad-hoc, manual and static standard web-service languages such as WSDL, BPEL and WS-CDL [3, 7]. The main objective of the work reported in this thesis is thus to leverage the development of service-oriented business applications towards more reliability and dynamic adaptability, placing emphasis on the use of business rules to govern activities, while composing services. The best available software-engineering techniques for adaptability, mainly aspect-oriented mechanisms, are also to be integrated with advanced formal techniques. More specifically, the proposed approach consists of the following incremental steps. First, it models any business activity behaviour governing any service-oriented business process as Event-Condition-Action (ECA) rules. Then such informal rules are made more interaction-centric, using adapted architectural connectors. Third, still at the conceptual-level, with the aim of adapting such ECA-driven connectors, this approach borrows aspect-oriented ideas and mechanisms, and proposes to intercept events, select the properties required for interacting entities, explicitly and separately execute such ECA-driven behavioural interactions and finally dynamically weave the results into the entities involved. To ensure compliance and to preserve the implementation of this architectural conceptualisation, the work adopts the Maude language as an executable operational formalisation. For that purpose, Maude is first endowed with the notions of components and interfaces. Further, the concept of ECA-driven behavioural interactions are specified and implemented as aspects. Finally, capitalising on Maude reflection, the thesis demonstrates how to weave such interaction executions into associated services.

Web services composition is emerging as a promising technology for the effective automation of application-to-application collaborations. The application integration problems have been subject of much research in the past years. However, with growth in importance of business process automation and highly dynamic nature of the Internet, this research has taken on a new significance and importance. Adequate solutions to this problem will be very important to make enterprise systems more flexible, robust and usable in the future. In this dissertation, we present a novel approach for the declarative definition and scalable orchestration of composite Web services in large, autonomous, heterogeneous, and dynamic environments. We first propose a composition model for composing Web services in a personalized and adaptive manner. We model composite Web services based on statecharts. To cater for large amounts of dynamic Web services, we use the concept of service community that groups services together and is responsible for the runtime selection of services against user's preferences. We use the concept of process schema that specific users can adjust with their personal preferences. A set of exception handling policies can be specified to proactively react to runtime exceptions. We then propose a tuple space based service orchestration model for distributed, self-managed composite services execution. We introduce the concept of execution controller that is associated with a service and is responsible for monitoring and controlling service executions. The knowledge required by a controller is statically extracted from the specification of personalized composite services. We also present techniques for robust Web services provisioning. The techniques presented in this dissertation are implemented in Self-Serv, a prototype that provides a set of tools for Web service composition and execution. Finally, we conduct an extensive usability and performance study of the proposed techniques. The experimental results reveal that our system i) provides an efficient support for specifying, deploying, and accessing composite services; ii) is more scalable and outperforms the centralized approach when the exchanged messages become bigger; and iii) is more robust and adaptive in highly dynamic environments.

Le processus de composition des services Web joue un rôle important dans la réalisation des architectures orientées services (SOA). Dans les environnements dynamiques dans lesquels des informations con-textuelles changent souvent, le processus de composition est souvent affec-té pendant les phases de conception et d’exécution. Ce processus devrait par conséquence être en mesure de s'adapter aux changements en temps de conception et exécution. A présent, les architectures orientées services et les mécanismes automatiques de composition de services Web ne parviennent pas à faire face aux changements continus et imprévisibles. Construire des architectures orientées services qui s'adaptent aux changements dans des environnements dynamiques révèle un défi pour les processus de com-position de services Web. En outre, les processus de composition actuelles offrent un support limité pour les utilisateurs professionnels de spécifier leurs exigences métier afin générer automatiquement les processus métiers (services Web composites). Par cela, l'écart entre les exigences fonction-nelles et non-fonctionnelles au niveau métier et les exigences techniques liées aux mécanismes de composition de services Web augmentent la com-plexité du développement d'applications ou de processus métier adaptés aux environnements dynamiques. Pour remédier à ces défis, nous introduisons le concept de rési-lience appliqué à l'informatique orientée services (nommé SOC résilient) afin de construire des applications et processus métier dynamiques en res-pectant les exigences métier dans des environnements dynamiques. La SOA résilient est conçue comme un ensemble de modèles qui affectent, et sont affectées par, d’autres modèles. Dans cette thèse, nos contributions, qui se concentrent en particulier sur le modèle d’exigence de composition et le modèle de composition des services Web, composent trois parties princi-pales: tout d'abord le modèle de d’exigence est modélisé aux trois niveaux, i.e., métier, capacité, et règle. Particulièrement, le modèle de d’exigence métier offre aux utilisateurs un langage structuré à base de langage naturelle pour spécifier les processus métier; d'autre part, un processus de trans-formation dérive par transformation un modèle d’exigence de composition à base de règles. Chaque règle représente un ensemble de contraintes multi-objectives concernant différentes variables liées au processus de composi-tion et à son environnement dynamique. Troisièmement, une approche ad-hoc de composition des services Web a été développée pour construire de services composites sans plans de composition prédéfinis dans des environ-nements dynamiques. L’approche de transformation de modèle-à-modèle génère les règles qui sont récursivement utilisées pour modifier ces modèles et ensuite replanifiés une composition ad-hoc de services Web
Due to the distributed and asynchronous nature of Web services, the Web service composition process plays an important role in achieving SOC. In dynamic environments by which contextual information such as Web service properties and composition requirements often change, the composition process is thus affected and, consequently, should be able to adapt composite applications to changes at design time and runtime. Un-fortunately, current Service-Oriented Architecture (SOA) and Web service composition approaches lack of the ability to deal with continuous and un-predictable changes. Building resilient service-oriented architectures that are adaptable to endogenous and exogenous changes in dynamic environments reveal a drastic challenge to current composition processes. In addition, current composition processes provide a limited support for business users to specify their requirements in business languages to automatically compose business processes (i.e., composite services). By such, the gap be-tween business requirements and composition requirements related to Web services increases the complexity of developing adaptable SOA-based ap-plications and processes in dynamic environments. To overcome these challenges, we introduce the concept of Resili-ent Service-Oriented Computing (rSOC) to construct resilient SOA-based applications driven by business requirements in dynamic environments. To this end, the resilient SOA is defined as a set of models that affect and are affected by each other, and relies on a model-to-model transformation ap-proach to ensure SOA adaptability and evolution. In this thesis, we particu-larly focus on two models: a three-level composition requirement model and a Web service composition model, to establish the foundation for a re-silient SOA as follows: firstly, composition requirements are modeled in three levels, i.e., business-centric, capability-focused and rule-driven. Par-ticularly the business-centric requirement model provides business users with a structured natural language to specify requirements; secondly, a two-phase requirement transformation process builds the rule-driven Web ser-vice composition requirement model from the business-centric requirement model as set of composition rules, expressing multi-objective constraints that affect the composition process and its dynamic environment; thirdly, an ad-hoc Web service composition approach is introduced to flexibly con-struct composite services without predefined composition plans. Particularly, composition rules generated in composition process may affect other model(s) in the resilient SOA, such as composition requirement model, and recursively invoke the model-to-model transformation approach to replan the ad-hoc Web service composition approach

L'Orienté Service (SOA) est un paradigme de conception qui facilite la construction d’applications extensibles et reconfigurables basées sur des artefacts réutilisables qui sont les services. Ceux-ci sont structurés via des interfaces bien définies et publiables et qui peuvent être dynamiquement découvertes.Beaucoup d’approches ont été proposées dans la littérature pour la réingénierie d’applications existantes développées dans des paradigmes pré-services, principalement l’orienté objet, vers SOA. L’objectif est de permettre de sauvegarder la valeur métier de ces d’applications tout en leur permettant de bénéficier des avantages de SOA. Le problème est que ces approches s'appuient sur des critères ad-hoc pour identifier correctement des services dans le code source des applications existantes.Par ailleurs, l'une des caractéristiques les plus distinctives d'une application orientée service est sa capacité de se reconfigurer dynamiquement et d'adapter son comportement en fonction de son contexte d'exécution. Cependant, dans les langages de description d'architecture (ADL) existants dont l’aspect de reconfiguration et pris en compte, les règles de reconfiguration sont représentées d'une manière ad-hoc; en général, elles ne sont pas modélisées d'une manière explicite mais enfouillées dans la description de l'architecture. D'une part, ceci engendre une difficulté de la gestion de la reconfiguration dynamique au niveau de l'architecture et d’autre part, la traçabilité de la description de la reconfiguration dynamique à travers les différents niveaux d'abstraction est difficile à représenter et à gérer.Afin de surmonter les problèmes précédents, nous proposons dans le cadre de cette thèse deux contributions. D'abord, nous proposons une approche d'identification de services basée sur un modèle de qualité où les caractéristiques des services sont étudiées, raffinées et réifiées en une fonction que nous utilisons pour mesurer la validité sémantique de ces services. La deuxième contribution consiste en une proposition d'un langage de description d'architecture orientée service (ADL) qui intègre la description de la variabilité architecturale. Dans cette ADL les services qui peuvent constituer l’architecture, les éléments de contexte dont les changements d’état sont à l’origine des changements architecturaux, les variantes des éléments architecturaux sélectionnées en fonction des états des éléments de contexte et le comportement architectural dynamique sont ainsi spécifiés de façon modulaire
Service Oriented Architecture (SOA) is an architectural design paradigm which facilitates building and composing flexible, extensible and reusable service-oriented assets. These latter are encapsulated behind well-defined and published interfaces that can be dynamically discovered by third-party services. Before the advent of SOA, several software systems were developed using older technologies. Many of these systems still afford a business value, however they suffer from evolution and maintenance problems. It is advantageous to modernize those software systems towards service-based ones. In this sense, several re-engineering techniques propose migrating object-oriented applications towards SOA. Nonetheless, these approaches rely on ad-hoc criteria to correctly identify services in object-oriented legacy source code.Besides, one of the most distinguishing features of a service-oriented application is the ability to dynamically reconfigure and adjust its behavior to cope with changing environment during execution. However, in existing architecture description languages handling this aspect, reconfiguration rules are represented in an ad-hoc manner; reconfiguration scenarios are often implicit. This fact hinders a full management of dynamic reconfiguration at architecture level. Moreover, it constitutes a challenge to trace dynamic reconfiguration description/management at different levels of abstraction.In order to overcome the aforementioned problems, our contributions are presented in two axes: First, in the context of migrating legacy software towards SOA, we propose a service identification approach based on a quality measurement model, where service characteristics are considered, refined to measurable metrics in order to measure the semantic correctness of identified services. The second axis is dedicated to an Architecture Description Language (ADL) proposition that describes a variant-rich service-based architecture. In this modular ADL, dynamic reconfigurations are specified at architecture level. Moreover, the description is enriched with context and variability information, in order to enable a variability-based self-reconfiguration of architecture in response to context changes at runtime

Les architectures dynamiques orientées services ( D-SOA) se concentrent sur les interactions client-serveur à couplage faible, où les deux peuvent apparaître et disparaître à l'exécution. Notre objectif est de concevoir des systèmes de surveillance pour ces architectures. Comme les systèmes de surveillance classiques sont statiquement injectés dans les services surveillés, ils ne peuvent pas gérer correctement le cycle de vie des services d'exécution. En outre, quand un service est remplacé par un autre service, d'autres services peuvent toujours utiliser l'ancienne référence. Cette référence vers un service absent, lorsqu'elle est gardée en mémoire, peut induire des comportements non désirés. Cette thèse contribue à la conception d'un système de surveillance de l'utilisation des services, qui soit résistant à la dynamique de la plateforme et qui soit en mesure de faire face à l'utilisation des références obsolètes. Ce but est atteint en trois étapes. Tout d'abord, en considérant le caractère dynamique des systèmes SOA dans un environnement ouvert, nous concevons une approche de monitoring résistant au la dynamique de la plateforme. Nous identifions deux propriétés clés du système de surveillance à couplage faible: résilience à la dynamicité, c'est-à-dire qu'un moniteur d'interface et son état sont maintenus en mémoire et transférés à un nouveau service lors de la disparition d'un service utilisé, et exhaustivité, c'est-à-dire qu'un service surveillé ne peut pas contourner les observations du moniteur. Ensuite, pour éviter l'usage de références vers des services qui ne sont plus actifs, nous proposons un service de sécurité côté client (SSU Layer), qui permet de traiter ce problème de manière transparente. Si un service utilisé disparaît, la couche SSU peut soit substituer le service de manière transparente, soit lever une exception pour avertir explicitement le client. Cette couche SSU est basée sur une approche transactionnelle qui vise à préserver la cohérence des services actifs. Enfin, nous proposons d'intégrer les deux approches dans un nouveau système de surveillance (NewMS). Les NewMS hérite des principes des deux systèmes précédents: la résilience à la dynamicité, l'exhaustivité et la tolérance aux fautes. Il peut dynamiquement surveiller l'utilisation de services et traiter les références obsolètes de manière transparente. Ces trois propositions sont implémentées dans la plateforme OSGi. Nous avons développé une application simple qui simule un système de réservation de place, qui est monitoré par notre systèmes. Nous avons également proposé différentes spécifications pour ce système. Nos résultats démontrent que le coût d'observation de notre moniteur est proche du coût d'un monitor classique, ne prenant pas en compte les problématiques liées à la dynamique.

Workflow Management Systems (WfMSs) are used to support the modelling, analysis, and enactment of business processes. The key benefits WfMSs seek to bring to an organisation include improved efficiency, better process control and improved customer service, which are realised by modelling rigidly structured business processes that in turn derive well-defined workflow process instances. However, the proprietary process definition frameworks imposed by WfMSs make it difficult to support (i) dynamic evolution and adaptation (i.e. modifying process definitions during execution) following unexpected or developmental change in the business processes being modelled; and (ii) exceptions, or deviations from the prescribed process model at runtime, even though it has been shown that such deviations are a common occurrence for almost all processes. These limitations imply that a large subset of business processes do not easily translate to the 'system-centric' modelling frameworks imposed. This research re-examines the fundamental theoretical principles that underpin workflow technologies to derive an approach that moves forward from the productionline paradigm and thereby offers workflow management support for a wider range of work environments. It develops a sound theoretical foundation based on Activity Theory to deliver an implementation of an approach for dynamic and extensible flexibility, evolution and exception handling in workflows, based not on proprietary frameworks, but on accepted ideas of how people actually perform their work activities. The approach produces a framework called worklets to provide an extensible repertoire of self-contained selection and exception-handling processes, coupled with an extensible ripple-down rule set. Using a Service-Oriented Architecture (SOA), a selection service provides workflow flexibility and adaptation by allowing the substitution of a task at runtime with a sub-process, dynamically selected from its repertoire depending on the context of the particular work instance. Additionally, an exceptionhandling service uses the same repertoire and rule set framework to provide targeted and multi-functional exception-handling processes, which may be dynamically invoked at the task, case or specification level, depending on the context of the work instance and the type of exception that has occurred. Seven different types of exception can be handled by the service. Both expected and unexpected exceptions are catered for in real time. The work is formalised through a series of Coloured Petri Nets and validated using two exemplary studies: one involving a structured business environment and the other a more creative setting. It has been deployed as a discrete service for the well-known, open-source workflow environment YAWL, and, having a service orientation, its applicability is in no way limited to that environment, but may be regarded as a case study in service-oriented computing whereby dynamic flexibility and exception handling for workflows, orthogonal to the underlying workflow language, is provided. Also, being open-source, it is freely available for use and extension.

Doutoramento em Informática
A natureza dinâmica de cenários como Ambient Assisting Living e ambientes pervasivos e ubíquos criam contextos de avaliação exigentes que não são completamente considerados pelos métodos existentes. Esta tese defende que são possíveis avaliações que tenham em consideração a natureza dinâmica e heterogénea de ambientes reactivos, integrando aspectos como percepção e dependência de contexto, adaptabilidade ao utilizador, gestão de eventos complexos e diversidade de ambientes. O principal objectivo deste trabalho foi desenvolver uma solução que forneça aos avaliadores a possibilidade de definir e aplicar avaliações a utilizadores suportadas por um modelo de avaliação flexível, permitindo a criação e reutilização de instrumentos e especificações de avaliação sem modificar a infraestrutura geral. Para atingir este objectivo foi seguida uma abordagem de engenharia envolvendo: a) definição de requisitos; b) conceptualização de uma solução geral contendo um paradigma, uma metodologia, um modelo e uma arquitectura; c) implementação dos componentes nucleares; d) desenvolvimento e teste de provas de conceito. Como resultado principal obteve-se uma solução de avaliação dinâmica para ambientes reactivos integrando três partes essenciais: um paradigma, uma metodologia e uma arquitectura de suporte. No seu conjunto, esta solução permite a criação de sistemas de avaliação escaláveis, flexíveis e modulares para concepção de avaliações e aplicação em ambientes reactivos.
The dynamic nature of scenarios such as Ambient Assisting Living and Ubiquitous and Pervasive environments turns them into challenging evaluation contexts not properly addressed by existing methods. We argue that it is possible to have evaluations that take into consideration the dynamic and heterogeneous nature of reactive environments by integrating aspects such as context-awareness, user adaptability, complex event handling, and environment diversity. In this context, the main objective of this work was to develop a solution providing evaluators with the ability to de ne and apply evaluation tests to end-users supported by a exible evaluation model allowing them to create or reuse evaluation instruments and speci cations without changing the infrastructure or the need for other logistical necessities. To pursue this goal, we adopted an engineering approach encompassing: a) requirements de nition; b) conceptualization of a general solution comprising paradigm, methodology, model, and architecture; c) implementation of its core components; and d) development and deployment of a proof of concept. The result was a dynamic evaluation solution for reactive environments based on three major parts: a paradigm, a methodology and its model, and a support architecture. Altogether, they enable the creation of scalable, exible and modular evaluation systems for evaluation design and application in reactive environments. Overall, we consider that the proposed approach, due to its exibility and scope, widely surpasses the goals considered on the onset of this work. With a broad range of features it establishes itself as a general purpose evaluation solution, potentially applicable to a wider range of scenarios, and fostering the creation of ubiquitous and continuous evaluation systems.

Cloud computing represents a fundamental change in the way organizations acquire technological resources (e.g., hardware, development and execution environments, applications); where, instead of buying them, they acquire remote access to them in the form of cloud services supplied through the Internet. Among the main characteristics of cloud computing is the allocation of resources in an agile and elastic way, reserved or released depending on the demand of the users or applications, enabling the payment model based on consumption metrics. The development of cloud applications mostly follows an incremental approach, where the incremental delivery of functionalities to the client changes - or reconfigures - successively the current architecture of the application. Cloud providers have their own standards for both implementation technologies and service management mechanisms, requiring solutions that facilitate: building, integrating and deploying portable services; interoperability between services deployed across different cloud providers; and continuity In the execution of the application while its architecture is reconfigured product of the integration of the successive increments. The principles of the model-driven development approach, the architectural style service-oriented architectures, and the dynamic reconfiguration play an important role in this context. The hypothesis of this doctoral thesis is that model-driven development methods provide cloud service developers with abstraction and automation mechanisms for the systematic application of the principles of model engineering during the design, implementation, and incremental deployment of cloud services, facilitating the dynamic reconfiguration of the service-oriented architecture of cloud applications. The main objective of this doctoral thesis is therefore to define and validate empirically DIARy, a method of dynamic and incremental reconfiguration of service-oriented architectures for cloud applications. This method will allow specifying the architectural integration of the increment with the current cloud application, and with this information to automate the derivation of implementation artifacts that facilitate the integration and dynamic reconfiguration of the service architecture of the cloud application. This dynamic reconfiguration is achieved by running reconfiguration artifacts that not only deploy / un-deploy increment's services and orchestration services between services of the increment with the services of the current cloud application; but also, they change the links between services at runtime. A software infrastructure that supports the activities of the proposed method has also been designed and implemented. The software infrastructure includes the following components: i) a set of DSLs, with their respective graphical editors, that allow to describe aspects related to the architectural integration, implementation and provisioning of increments in cloud environments; ii) transformations that generate platform-specific implementation and provisioning models; (iii) transformations that generate artifacts that implement integration logic and orchestration of services, and scripts of provisioning, deployment, and dynamic reconfiguration for different cloud vendors. This doctoral thesis contributes to the field of service-oriented architectures and in particular to the dynamic reconfiguration of cloud services architectures in an iterative and incremental development context. The main contribution is a well-defined method, based on the principles of model-driven development, which makes it easy to raise the level of abstraction and automate, through transformations, the generation of artifacts that perform the dynamic reconfiguration of cloud applications.
La computación cloud representa un cambio fundamental en la manera en la que las organizaciones adquieren recursos tecnológicos (p. ej., hardware, entornos de desarrollo y ejecución, aplicaciones); en donde, en lugar de comprarlos adquieren acceso remoto a ellos en forma de servicios cloud suministrados a través de Internet. Entre las principales características de la computación cloud está la asignación de recursos de manera ágil y elástica, reservados o liberados dependiendo de la demanda de los usuarios o aplicaciones, posibilitando el modelo de pago basado en métricas de consumo. El desarrollo de aplicaciones cloud sigue mayoritariamente un enfoque incremental, en donde la entrega incremental de funcionalidades al cliente cambia - o reconfigura - sucesivamente la arquitectura actual de la aplicación. Los proveedores cloud tienen sus propios estándares tanto para las tecnologías de implementación como para los mecanismos de gestión de servicios, requiriéndose soluciones que faciliten: la construcción, integración y despliegue de servicios portables; la interoperabilidad entre servicios desplegados en diferentes proveedores cloud; y la continuidad en la ejecución de la aplicación mientras su arquitectura es reconfigurada producto de la integración de los sucesivos incrementos. Los principios del enfoque de desarrollo dirigido por modelos, del estilo arquitectónico de arquitecturas orientadas a servicios y de la reconfiguración dinámica cumplen un papel importante en este contexto. La hipótesis de esta tesis doctoral es que los métodos de desarrollo dirigido por modelos brindan a los desarrolladores de servicios cloud mecanismos de abstracción y automatización para la aplicación sistemática de los principios de la ingeniería de modelos durante el diseño, implementación y despliegue incremental de servicios cloud, facilitando la reconfiguración dinámica de la arquitectura orientada a servicios de las aplicaciones cloud. El objetivo principal de esta tesis doctoral es por tanto definir y validar empíricamente DIARy, un método de reconfiguración dinámica e incremental de arquitecturas orientadas a servicios. Este método permitirá especificar la integración arquitectónica del incremento con la aplicación cloud actual, y con esta información automatizar la derivación de los artefactos de implementación que faciliten la integración y reconfiguración dinámica de la arquitectura de servicios de la aplicación cloud. Esta reconfiguración dinámica se consigue al ejecutar los artefactos de reconfiguración que no solo despliegan/repliegan los servicios del incremento y servicios de orquestación entre los servicios del incremento con los servicios de la aplicación cloud actual; sino también, cambian en tiempo de ejecución los enlaces entre servicios. También se ha diseñado e implementado una infraestructura software que soporta las actividades del método propuesto e incluye los siguientes componentes: i) un conjunto de DSLs, con sus respectivos editores gráficos, que permiten describir aspectos relacionados a la integración arquitectónica, implementación y aprovisionamiento de incrementos en entornos cloud; ii) transformaciones que generan modelos de implementación y aprovisionamiento; iii) transformaciones que generan artefactos que implementan la lógica de integración y orquestación de servicios, y scripts de aprovisionamiento, despliegue y reconfiguración dinámica específicos para distintos proveedores cloud. Esta tesis doctoral contribuye al campo de las arquitecturas orientadas a servicios y en particular a la reconfiguración dinámica de arquitecturas de servicios cloud en contextos de desarrollo iterativo e incremental. El principal aporte es un método bien definido, basado en los principios del desarrollo dirigido por modelos, que facilita elevar el nivel de abstracción y automatizar por medio de transformaciones la generación de artefactos que real
La computació cloud representa un canvi fonamental en la manera en què les organitzacions adquirixen recursos tecnològics (ej., maquinari, entorns de desplegament i execució, aplicacions) ; on, en compte de comprar-los adquirixen accés remot a ells en forma de servicis cloud subministrats a través d'Internet. Entre les principals característiques de la computació cloud els recursos cloud són assignats de manera àgil i elàstica, reservats o alliberats depenent de la demanda dels usuaris o aplicacions, possibilitant el model de pagament basat en mètriques de consum. El desenrotllament d'aplicacions cloud seguix majoritàriament un enfocament incremental, on l'entrega incremental de funcionalitats al client canvia - o reconfigura - successivament l'arquitectura actual de l'aplicació. Els proveïdors cloud tenen els seus propis estàndards tant per a les tecnologies d'implementació com per als mecanismes de gestió de servicis, requerint-se solucions que faciliten: la construcció, integració i desplegament de servicis portables; la interoperabilitat entre servicis desplegats en diferents proveïdors cloud; i la continuïtat en l'execució de l'aplicació mentres la seua arquitectura és reconfigurada producte de la integració dels successius increments. Els principis de l'enfocament de desenrotllament dirigit per models, de l'estil arquitectònic d'arquitectures orientades a servicis i de la reconfiguració dinàmica complixen un paper important en este context. La hipòtesi d'esta tesi doctoral és que els mètodes de desenrotllament dirigit per models brinden als desenvolupadors de servicis cloud mecanismes d'abstracció i automatització per a l'aplicació sistemàtica dels principis de l'enginyeria de models durant el disseny, implementació i desplegament incremental de servicis cloud, facilitant la reconfiguració dinàmica de l'arquitectura orientada a servicis de les aplicacions cloud. L'objectiu principal d'esta tesi doctoral és per tant de definir i validar empí-ricamente DIARy, un mètode de reconfiguració dinàmica i incremental d'arquitectures orientades a servicis per a aplicacions cloud. Este mètode permetrà especificar la integració arquitectònica de l'increment amb l'aplicació cloud actual, i amb esta informació automatitzar la derivació dels artefactes d'implementació que faciliten la integració i reconfiguració dinàmica de l'arquitectura de servicis de l'aplicació cloud. Esta reconfi-guración dinàmica s'aconseguix a l'executar els artefactes de reconfiguració que no sols despleguen/repleguen els servicis de l'increment i servicis d'orquestració entre els servicis de l'increment amb els servicis de l'aplicació cloud actual; sinó també, canvien en temps d'execució els enllaços entre servicis. També s'ha dissenyat i implementat una infraestructura programari que suporta les activitats del mètode proposat i inclou els següents components: i) un conjunt de DSLs, amb els seus respectius editors gràfics, que permeten descriure aspectes relacionats a la integració arquitectònica, implementació i aprovisionament en entorns cloud dels increments; ii) transformacions que generen models d'implementació i aprovisionament específics de la plataforma a partir dels models d'integració d'alt nivell; iii) transformacions que generen artefactes que implementen la lògica d'integració i orquestració de servicis, i scripts d'aprovisionament, desplegament i reconfiguració dinàmica específics per a distints proveïdors cloud. Esta tesi doctoral contribuïx al camp de les arquitectures orientades a servicis i en particular a la reconfiguració dinàmica d'arquitectures de servicis cloud en contextos de desenrotllament iteratiu i incremental. La principal aportació és un mètode ben definit, basat en els principis del desenrotllament dirigit per models, que facilita elevar el nivell d'abstracció i automatitzar per mitjà de transformacions la generació d'artefactes que r
Zuñiga Prieto, MÁ. (2017). Reconfiguración Dinámica e Incremental de Arquitecturas de Servicios Cloud Dirigida por Modelos [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86288
TESIS

Companies operating in a dynamic environment need to continuously adapt their information systems to changing business processes and associated information needs. Viewed from a microperspective, business users are managing and executing business processes with standard enterprise resource planning systems (ERPs) based on service-oriented architectures on a daily basis but are often not able to adapt the software they use to their individual needs and working practices. This chapter presents the development and evaluation of a prototypic environment that enables users to create enterprise widgets, such as enterprise mash-ups, with tailorability (i.e., they can be tailored to the users’ personal information needs), without the users needing programming knowledge. This environment allows the mashing up of enterprise resources via a lightweight visual-design technique. The evaluation of the prototype in business contexts indicates its usefulness and usability.