Different types of web resources, such as Web Services, HTTP-based APIs and websites, can be located on the web to provide various services, such as information access and online banking. Such services are the basic building blocks to compose more complex functionality that cannot be achieved by a single service. Many service-oriented applications can be composed to fulfill similar functional requirements. Among various applications, a set of services can be frequently used together to deliver a unique functionality. Such set of services are called a service composition pattern. More specifically, a service composition pattern consists of a set of services and the control flow among the services. The reuse of the service composition patterns can facilitate the composition of new applications, improve existing applications and optimize maintenance process of services. To facilitate the identification and reuse of service composition patterns, we propose an approach that mines the service composition patterns from execution logs produced by service-oriented applications during runtime. Since the execution logs can be produced by heterogeneous web resources, we propose a unified description schema to describe various web resources in order to identify functionally similar services of different types. This helps reveal complete service composition patterns. Then we identify frequently associated services using Apriori algorithm and heuristics. Finally, we recover the control flow among the services using the event graph and process mining techniques. The effectiveness of the approach is evaluated through two case studies. The result shows that the unified description schema facilitates the identification of similar services of different types and our approach can effectively identify service composition patterns. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-09-29 18:08:07.55

Healthcare Informatics suffers from the lack of information exchange among domain partners. Allowing cooperation among distributed and heterogeneous applications is a major need of current healthcare information systems. Beyond the communication and integration problems, medical information itself is by nature complex, combined with data and knowledge. The increasing number of standards and representation of the same data in different structures using these standards constitute another problem in the domain. Platform and implementation independency makes Web service technology the natural way to solve the interoperability problems in the healthcare domain. Standardizing the access to data through WSDL and SOAP rather than standardizing the electronic health record will help to overcome the integration problems among different standards in medical information systems. However, introducing Web services to the healthcare systems will not suffice to solve the problems in the domain unless the semantics of the services are exploited. This thesis aims to show that by generating web services and classifying these services through their functionalities, it is possible to achieve the interoperability among healthcare institutes, such as hospitals. The designed system is based on Artemis P2P Framework, and the annotation of the system is realized in the same framework.

Web services introduce a new paradigm for distributed computing, and the technology that it introduces constructs a new type of Web application. Web services can be described as any software that makes its discovery and invocation available over the Internet, and uses a standardized XML messaging system. The term peer-to-peer refers to a class of decentralized systems enabling the access of shared resources available on peers that are acting both as client and as server. In this work, a peer-to-peer approach is used to expoit Web service technologies by providing Web service security for JXTA peer-to-peer networks. JXTA is a network programming environment that has particularly been designed for the peer-to-peer platform. In order to achieve the goal of secure Web services, the specifications &ldquo / WSSecurity&rdquo / , &ldquo / XML Key Management Specification&rdquo / , &ldquo / WS-Trust&rdquo / and &ldquo / WSSecurityPolicy&rdquo / are exploited. &ldquo / WS-Security&rdquo / is primarily a specification for an XML-based security metadata container, and is a building block for the specifications &ldquo / WS-Trust&rdquo / and &ldquo / WS-SecurityPolicy&rdquo / . &ldquo / WS-Trust&rdquo / defines the process of how to acquire security tokens. Within the peer-to-peer network that is proposed with this work, a peer is dedicated to act as a &ldquo / trusted third party&rdquo / and to manage the processes for incorporating the security of public-key infrastructure, which is defined by &ldquo / XML Key Management Specification&rdquo / . In addition, the same peer is dedicated to manage to acquire security tokens, which is defined by &ldquo / WS-Trust&rdquo / . As for &ldquo / WS-SecurityPolicy&rdquo / , Web service invoking peers conform to this specification that specifies how to define security assertions stating Web service provider&rsquo / s preferences and requirements. This work realizes and achieves the necessity of bringing together the technologies mentioned above in order to propose an architecture of secure SOAP messaging for Web service invocation in peer-to-peer environment that is provided by the JXTA framework. The work presented in this thesis is realized as a part of the SATINE project funded by the European Commission.

A web service is a collection of functions that are packaged as a single entity and published to the network for use by other programs. Web services are building blocks for creating open distributed systems, and allow companies and individuals to quickly and cheaply make their digital assets available worldwide. With considerable interoperability, privacy management becomes an inevitable concern of the web services. Companies and individuals should be able to restrict the information available about themselves and specify the use of that information in order to protect their confidentiality. In the thesis, a privacy framework has been designed and implemented in order to prepare and match privacy documents for web services. Privacy documents are prepared based upon message ontologies which describe the input data of web services. Service requestors and providers prepare their own privacy documents which are going to be checked before the web service transaction begins. Privacy content has been derived from the World Wide Web Consortium&rsquo / s Platform for Privacy Preferences specification.

With the advent of Service Oriented Architecture, Web Services have gained tremendous popularity. Due to the availability of a large number of Web services, finding an appropriate Web service according to the requirement of the user is a challenge. This warrants the need to establish an effective and reliable process of Web service discovery. A considerable body of research has emerged to develop methods to improve the accuracy of Web service discovery to match the best service. The process of Web service discovery results in suggesting many individual services that partially fulfil the user’s interest. By considering the semantic relationships of words used in describing the services as well as the use of input and output parameters can lead to accurate Web service discovery. Appropriate linking of individual matched services should fully satisfy the requirements which the user is looking for. This research proposes to integrate a semantic model and a data mining technique to enhance the accuracy of Web service discovery. A novel three-phase Web service discovery methodology has been proposed. The first phase performs match-making to find semantically similar Web services for a user query. In order to perform semantic analysis on the content present in the Web service description language document, the support-based latent semantic kernel is constructed using an innovative concept of binning and merging on the large quantity of text documents covering diverse areas of domain of knowledge. The use of a generic latent semantic kernel constructed with a large number of terms helps to find the hidden meaning of the query terms which otherwise could not be found. Sometimes a single Web service is unable to fully satisfy the requirement of the user. In such cases, a composition of multiple inter-related Web services is presented to the user. The task of checking the possibility of linking multiple Web services is done in the second phase. Once the feasibility of linking Web services is checked, the objective is to provide the user with the best composition of Web services. In the link analysis phase, the Web services are modelled as nodes of a graph and an allpair shortest-path algorithm is applied to find the optimum path at the minimum cost for traversal. The third phase which is the system integration, integrates the results from the preceding two phases by using an original fusion algorithm in the fusion engine. Finally, the recommendation engine which is an integral part of the system integration phase makes the final recommendations including individual and composite Web services to the user. In order to evaluate the performance of the proposed method, extensive experimentation has been performed. Results of the proposed support-based semantic kernel method of Web service discovery are compared with the results of the standard keyword-based information-retrieval method and a clustering-based machine-learning method of Web service discovery. The proposed method outperforms both information-retrieval and machine-learning based methods. Experimental results and statistical analysis also show that the best Web services compositions are obtained by considering 10 to 15 Web services that are found in phase-I for linking. Empirical results also ascertain that the fusion engine boosts the accuracy of Web service discovery by combining the inputs from both the semantic analysis (phase-I) and the link analysis (phase-II) in a systematic fashion. Overall, the accuracy of Web service discovery with the proposed method shows a significant improvement over traditional discovery methods.

Com o crescimento da demanda por aplicações orientadas a serviços, a complexidade da gestão de mudanças em serviços aumenta cada vez mais. Nesse contexto, provedores de portfólios de serviços têm como objetivo a minimização do impacto de tais mudanças para os seus clientes. Os trabalhos existentes abordam essencialmente a mudança sob o viés técnico, lidando com técnicas de versionamento e determinação de compatibilidade. No entanto, os provedores possuem dilemas de decisão que vão além dos aspectos técnicos, abrangendo o impacto na perspectiva de negócios, considerando clientes afetados, receitas, custos, violações de SLA, entre outros. Este trabalho faz parte de um framework voltado para a análise da evolução de serviços considerando a perspectiva de uso dos mesmos. O presente trabalho propõe o uso de técnicas de Business Intelligence e Data Warehousing para apoiar a tomada de decisões orientadas a negócios na gestão do ciclo de vida de serviços. Em tal contexto, considera-se o cenário de portfólio de serviços e mudanças profundas, abrangendo cadeias de serviços e clientes diretos/indiretos. Este trabalho identifica e analisa requisitos de decisão, juntamente com indicadores financeiros e de uso relacionados à provisão de serviços. Um data warehouse é modelado para prover uma visão unificada e integrada de tais indicadores, de acordo com diferentes perspectivas de análise. Uma arquitetura para a extração, transformação e carga dos dados também é apresentada com a proposição de alternativas para lidar com a integração e heterogeneidade das fontes de dados. Através de um estudo de caso inspirado em um cenário real, demonstra-se como a análise do impacto é analisada através da abordagem proposta. / With the growing demand for service-oriented applications, the complexity of service change management is increasing. In this context, service providers aim at the minimal impact of changes to its clients. Existing work essentially addresses change decisions from a technical perspective, with versioning techniques and compatibility assessments. However, providers have decisional dilemmas that go beyond the technical aspects, addressing the business impact in terms of clients affected, revenues, costs, SLA penalties, among others. This work integrates a framework addressing the service evolution analysis based on service usage perspective. We propose the use of Business Intelligence and Data Warehousing techniques to support business-oriented decisions on the service life-cycle management. Our approach covers service portfolios and the deep change context, i.e. services consumed in large scale and direct/indirect clients. This work is centered on the identification and analysis of decisional requirements and financial and usage indicators related to the service provision business. A data warehouse is modeled to provide a unified and integrated view of these indicators, according to different analysis perspectives. An architecture to extract, transform and loading data also is presented, proposing alternatives to lead with the integration and the heterogeneity of the data sources. Through a case study inspired by a real world scenario, we demonstrate how change impact is analyzed according our approach.

Durante o ciclo de vida de um web service, diversas mudanças são feitas na sua interface, eventualmente causando incompatibilidades em relação aos seus clientes e ocasionando a quebra de suas aplicações. Os provedores precisam tomar decisões sobre mudanças em seus serviços frequentemente, muitas vezes sem um bom entendimento a respeito do efeito destas mudanças sobre seus clientes. Os trabalhos e ferramentas existentes não fornecem ao provedor um conhecimento adequado a respeito do uso real das funcionalidades da interface de um serviço, considerando os diferentes tipos de consumidores, o que impossibilita avaliar o impacto das mudanças. Este trabalho apresenta um framework para a descoberta de perfis de uso de serviços web, os quais constituem um modelo descritivo dos padrões de uso dos diferentes grupos de clientes do serviço, com relação ao uso das funcionalidades em sua interface. O framework auxilia no processo de descoberta de conhecimento através de tarefas semiautomáticas e parametrizáveis para a preparação e análise de dados de uso, minimizando a necessidade de intervenção do usuário. O framework engloba o monitoramento de interações de web services, a carga de dados de uso pré-processados em uma base de dados unificada, e a geração de perfis de uso. Técnicas de mineração de dados são utilizadas para agrupar clientes de acordo com seus padrões de uso de funcionalidades, e esses grupos são utilizados na construção de perfis de uso de serviços. Todo o processo é configurado através de parâmetros, permitindo que o usuário determine o nível de detalhe das informações sobre o uso incluídas nos perfis e os critérios para avaliar a similaridade entre clientes. A proposta é validada por meio de experimentos com dados sintéticos, simulados de acordo com características esperadas no comportamento de clientes de um serviço real. Os resultados dos experimentos demonstram que o framework proposto permite a descoberta de perfis de uso de serviço úteis, e fornecem evidências a respeito da parametrização adequada do framework. / During the life cycle of a web service, several changes are made in its interface, which possibly are incompatible with regard to current usage and may break client applications. Providers must make decisions about changes on their services, most often without insight on the effect these changes will have over their customers. Existing research and tools fail to input provider with proper knowledge about the actual usage of the service interface’s features, considering the distinct types of customers, making it impossible to assess the actual impact of changes. This work presents a framework for the discovery of web service usage profiles, which constitute a descriptive model of the usage patterns found in distinct groups of clients, concerning the usage of service interface features. The framework supports a user in the process of knowledge discovery over service usage data through semi-automatic and configurable tasks, which assist the preparation and analysis of usage data with the minimum user intervention possible. The framework performs the monitoring of web services interactions, loads pre-processed usage data into a unified database, and supports the generation of usage profiles. Data mining techniques are used to group clients according to their usage patterns of features, and these groups are used to build service usage profiles. The entire process is configured via parameters, which allows the user to determine the level of detail of the usage information included in the profiles, and the criteria for evaluating the similarity between client applications. The proposal is validated through experiments with synthetic data, simulated according to features expected in the use of a real service. The experimental results demonstrate that the proposed framework allows the discovery of useful service usage profiles, and provide evidences about the proper parameterization of the framework.

Atualmente existem muitos estudos sendo conduzidos na área de Home Care, onde casas providas com sensores e atuadores podem ajudar o paciente em suas tarefas diárias, mesmo aqueles portadores de doenças crônicas ou limitações cognitivas e físicas. No contexto de Home Care, dispositivos domésticos controláveis podem agir como atuadores. Um importante desafio nessa área é a coordenação desses atuadores, para que os mesmos possam ser utilizados na prestação de cuidados ao paciente em sua casa. Para prestar auxílio em tarefas, deve ser levado em consideração o contexto do paciente e dos dispositivos presentes na casa. Este trabalho apresenta uma nova abordagem, sensível ao contexto, para selecionar a funcionalidade, de um dispositivo, mais adequada para a execução de uma atuação em um ambiente de Home Care. Nessa abordagem, as funcionalidades dos dispositivos são representadas por serviços Web, e modelos de processos de negócio são utilizados como roteiros das atividades que devem ser realizadas para gerir uma determinada situação. Desta forma, o problema de selecionar dispositivos e funcionalidades adequadas para executar uma determinada atividade de atuação de um modelo de processo de negócio é tratado através da seleção de serviços Web com base em aspectos sintáticos, semânticos e contextuais. A abordagem é avaliada através da simulação de cenários de aplicação extraídos da literatura, de forma a verificar a sua viabilidade. / There are many studies currently being conducted within the field of Home Care, where houses fulfilled with actuators and sensors can help patients in their daily lives, even the ones who suffer from chronicle diseases or cognitive and physical disabilities. In the Home Care context, controllable domestic devices can perform as actuators. An important challenge to this area refers to the coordination of such actuators so they can be used to assist patients in their home. In order to assist the patient daily live we need to take into consideration the patient and the context of household devices. This work presents a novel context-aware approach for selecting the most appropriate device functionality to execute the actuation needed in a Home Care environment. In this approach, device functionalities are described and represented by Web services, and business process models are used as guidelines for the activities that should be realized to manage a determined situation. Therefore, the issue of selecting devices and adequate functionalities to execute determined activity in a business process model is treated as an approach to select Web services based on their syntactic and semantic aspects in a context-aware manner. The approach is evaluated by simulation of application scenarios extracted from the literature in order to check its viability.

Com o crescimento da demanda por aplicações orientadas a serviços, a complexidade da gestão de mudanças em serviços aumenta cada vez mais. Nesse contexto, provedores de portfólios de serviços têm como objetivo a minimização do impacto de tais mudanças para os seus clientes. Os trabalhos existentes abordam essencialmente a mudança sob o viés técnico, lidando com técnicas de versionamento e determinação de compatibilidade. No entanto, os provedores possuem dilemas de decisão que vão além dos aspectos técnicos, abrangendo o impacto na perspectiva de negócios, considerando clientes afetados, receitas, custos, violações de SLA, entre outros. Este trabalho faz parte de um framework voltado para a análise da evolução de serviços considerando a perspectiva de uso dos mesmos. O presente trabalho propõe o uso de técnicas de Business Intelligence e Data Warehousing para apoiar a tomada de decisões orientadas a negócios na gestão do ciclo de vida de serviços. Em tal contexto, considera-se o cenário de portfólio de serviços e mudanças profundas, abrangendo cadeias de serviços e clientes diretos/indiretos. Este trabalho identifica e analisa requisitos de decisão, juntamente com indicadores financeiros e de uso relacionados à provisão de serviços. Um data warehouse é modelado para prover uma visão unificada e integrada de tais indicadores, de acordo com diferentes perspectivas de análise. Uma arquitetura para a extração, transformação e carga dos dados também é apresentada com a proposição de alternativas para lidar com a integração e heterogeneidade das fontes de dados. Através de um estudo de caso inspirado em um cenário real, demonstra-se como a análise do impacto é analisada através da abordagem proposta. / With the growing demand for service-oriented applications, the complexity of service change management is increasing. In this context, service providers aim at the minimal impact of changes to its clients. Existing work essentially addresses change decisions from a technical perspective, with versioning techniques and compatibility assessments. However, providers have decisional dilemmas that go beyond the technical aspects, addressing the business impact in terms of clients affected, revenues, costs, SLA penalties, among others. This work integrates a framework addressing the service evolution analysis based on service usage perspective. We propose the use of Business Intelligence and Data Warehousing techniques to support business-oriented decisions on the service life-cycle management. Our approach covers service portfolios and the deep change context, i.e. services consumed in large scale and direct/indirect clients. This work is centered on the identification and analysis of decisional requirements and financial and usage indicators related to the service provision business. A data warehouse is modeled to provide a unified and integrated view of these indicators, according to different analysis perspectives. An architecture to extract, transform and loading data also is presented, proposing alternatives to lead with the integration and the heterogeneity of the data sources. Through a case study inspired by a real world scenario, we demonstrate how change impact is analyzed according our approach.

Durante o ciclo de vida de um web service, diversas mudanças são feitas na sua interface, eventualmente causando incompatibilidades em relação aos seus clientes e ocasionando a quebra de suas aplicações. Os provedores precisam tomar decisões sobre mudanças em seus serviços frequentemente, muitas vezes sem um bom entendimento a respeito do efeito destas mudanças sobre seus clientes. Os trabalhos e ferramentas existentes não fornecem ao provedor um conhecimento adequado a respeito do uso real das funcionalidades da interface de um serviço, considerando os diferentes tipos de consumidores, o que impossibilita avaliar o impacto das mudanças. Este trabalho apresenta um framework para a descoberta de perfis de uso de serviços web, os quais constituem um modelo descritivo dos padrões de uso dos diferentes grupos de clientes do serviço, com relação ao uso das funcionalidades em sua interface. O framework auxilia no processo de descoberta de conhecimento através de tarefas semiautomáticas e parametrizáveis para a preparação e análise de dados de uso, minimizando a necessidade de intervenção do usuário. O framework engloba o monitoramento de interações de web services, a carga de dados de uso pré-processados em uma base de dados unificada, e a geração de perfis de uso. Técnicas de mineração de dados são utilizadas para agrupar clientes de acordo com seus padrões de uso de funcionalidades, e esses grupos são utilizados na construção de perfis de uso de serviços. Todo o processo é configurado através de parâmetros, permitindo que o usuário determine o nível de detalhe das informações sobre o uso incluídas nos perfis e os critérios para avaliar a similaridade entre clientes. A proposta é validada por meio de experimentos com dados sintéticos, simulados de acordo com características esperadas no comportamento de clientes de um serviço real. Os resultados dos experimentos demonstram que o framework proposto permite a descoberta de perfis de uso de serviço úteis, e fornecem evidências a respeito da parametrização adequada do framework. / During the life cycle of a web service, several changes are made in its interface, which possibly are incompatible with regard to current usage and may break client applications. Providers must make decisions about changes on their services, most often without insight on the effect these changes will have over their customers. Existing research and tools fail to input provider with proper knowledge about the actual usage of the service interface’s features, considering the distinct types of customers, making it impossible to assess the actual impact of changes. This work presents a framework for the discovery of web service usage profiles, which constitute a descriptive model of the usage patterns found in distinct groups of clients, concerning the usage of service interface features. The framework supports a user in the process of knowledge discovery over service usage data through semi-automatic and configurable tasks, which assist the preparation and analysis of usage data with the minimum user intervention possible. The framework performs the monitoring of web services interactions, loads pre-processed usage data into a unified database, and supports the generation of usage profiles. Data mining techniques are used to group clients according to their usage patterns of features, and these groups are used to build service usage profiles. The entire process is configured via parameters, which allows the user to determine the level of detail of the usage information included in the profiles, and the criteria for evaluating the similarity between client applications. The proposal is validated through experiments with synthetic data, simulated according to features expected in the use of a real service. The experimental results demonstrate that the proposed framework allows the discovery of useful service usage profiles, and provide evidences about the proper parameterization of the framework.