9 research outputs found

    Privacy enhanced and web based service composition

    Get PDF
    Service selection is a key issue in the Future Internet, where applications are built by composing services and content offered by different service providers. Most existing service selection schemas only focus on the functional QoS properties of services such as throughput, latency and response time, or on their trust and reputation level. By contrast, the risk of privacy breaches arising from the selection of component services whose privacy policy is not compliant with customers’ privacy preferences is largely ignored. In this paper, we propose a novel privacy-preserving Web service composition and selection approach which (i) makes it possible to verify the compliance between users’ privacy requirements and providers’ privacy policies and (ii) ranks the composite Web services with respect to the privacy level they offer. We demonstrate our approach using a travel agency Web service as an example of service composition

    Ontological Map of Service Oriented Architecture Based on Zachman

    Get PDF
    Service orientation is an approach in the field of enterprise architecture, business information systems and software application that its main element is the service. Shared services is an organization model of sharing, across an organization. It enables collaboration among the functions/departments. Main motivations for shared services are sharing, promote efficiency, reduce cost, and support scalability. Despite of the widespread use of these two approaches in information technology, there is no tool to optimize the management of them. The aim of this study is Ontological map of service oriented architecture based on zachman framework to adapt it in the reference enterprise architecture framework through implementation ontology views on system architect software and as well as equivalent ontology component with UML diagrams. After the implementation of the suggested model, the results showed that ontology is a formal description and explicit display of objects, concepts and other entities in the relationship between them. In other words, there is a model that describe all that is in fact in to understandable language for the system. Thus the proposed establishes have association between all aspects of zachman framework, also to create a clear description of business concepts in the management of shared services and is effective to provide a unified platform for enterprise modeling

    Case based web services

    Full text link

    Demand driven web services

    Full text link
    Web services are playing a pivotal role in e-business, service intelligence, and service science. Demand-driven web services are becoming important for web services and service computing. However, many fundamental issues are still ignored to some extent. For example, what is the demand theory for web services, what is a demand-driven architecture for web services and what is a demand-driven web service lifecycle remain open. This chapter addresses these issues by examining fundamentals for demand analysis in web services, and proposing a demand-driven architecture for web services. It also proposes a demand-driven web service lifecycle for the main players in web services: Service providers, service requestors and service brokers, respectively. It then provides a unified perspective on demand-driven web service lifecycles. The proposed approaches will facilitate research and development of web services, e-services, service intelligence, service science and service computing

    ON THE FUNCTIONAL QUALITY OF SERVICE (FQOS) TO DISCOVER AND COMPOSE INTEROPERABLE WEB SERVICES

    No full text
    Despite its prevalence, the service-oriented architecture (SOA) still has an imperative challenge to achieve interoperability within and across enterprise applications. Minimal conditions for interoperability are: (1) to discover and plug in proper services for integration and (2) to support for seamless data exchanges between component services. A similarity-based approximate matching is a practical approach for both, in that the service discovery relies on functional matches between a query and service descriptions, and the seamless data exchange is granted by mapping information from a service to others. To these ends, this paper comprehensively investigates functional attributes of web services and their manipulation, and particularly highlights an information compatibility and mapping analysis. The functional quality of service (FQoS) allows service discovery and selection to step forward. Simulation results show that the present FQoS metrics are effective in service discovery, (C) 2008 Elsevier Ltd. All rights reserved.X1121sciescopu

    A comprehensive evaluation framework for system modernization : a case study using data services

    Get PDF
    Modernization is a solution to migrate cumbersome existing systems to a new architecture for improved longevity of business processes. Three modernization approaches exist. White-box and black-box modernization are distinct from one another. Grey-box modernization is a hybrid of the white-box and black-box approaches. Modernization can be utilised to create data services for a Service Oriented Architecture. Since it is unclear which modernization approach is more suitable for the development of data services, a comprehensive evaluation framework is proposed to evaluate which of the white- or black-box approaches is more suitable. The comprehensive framework consists of three evaluation components. Firstly, developer effort to modernize existing code is measured by acknowledged software metrics. Secondly, the quality of the data services is measured against identified Quality of Service criteria for data services in particular. Thirdly, the effectiveness of the modernized data services is measured through usability evaluations. By inspection of the combination of application of each of the evaluation components, a recommended approach is identified for the modernization of data services. The comprehensive framework was successfully employed to compare the white-box and black-box modernization approaches applied to a case study. Results indicated that had only a single evaluation component been used, inconclusive results of the more suitable approach may have been obtained. The findings of this research contribute a comprehensive evaluation framework which can be applied to compare modernization approaches and measure modernization success

    A comprehensive evaluation framework for system modernization : a case study using data services

    Get PDF
    Modernization is a solution to migrate cumbersome existing systems to a new architecture for improved longevity of business processes. Three modernization approaches exist. White-box and black-box modernization are distinct from one another. Grey-box modernization is a hybrid of the white-box and black-box approaches. Modernization can be utilised to create data services for a Service Oriented Architecture. Since it is unclear which modernization approach is more suitable for the development of data services, a comprehensive evaluation framework is proposed to evaluate which of the white- or black-box approaches is more suitable. The comprehensive framework consists of three evaluation components. Firstly, developer effort to modernize existing code is measured by acknowledged software metrics. Secondly, the quality of the data services is measured against identified Quality of Service criteria for data services in particular. Thirdly, the effectiveness of the modernized data services is measured through usability evaluations. By inspection of the combination of application of each of the evaluation components, a recommended approach is identified for the modernization of data services. The comprehensive framework was successfully employed to compare the white-box and black-box modernization approaches applied to a case study. Results indicated that had only a single evaluation component been used, inconclusive results of the more suitable approach may have been obtained. The findings of this research contribute a comprehensive evaluation framework which can be applied to compare modernization approaches and measure modernization success

    Coordination fiable de services de données à base de politiques actives

    Get PDF
    We propose an approach for adding non-functional properties (exception handling, atomicity, security, persistence) to services' coordinations. The approach is based on an Active Policy Model (AP Model) for representing services' coordinations with non-functional properties as a collection of types. In our model, a services' coordination is represented as a workflow composed of an ordered set of activities, each activity in charge of implementing a call to a service' operation. We use the type Activity for representing a workflow and its components (i.e., the workflow' activities and the order among them). A non-functional property is represented as one or several Active Policy types, each policy composed of a set of event-condition-action rules in charge of implementing an aspect of the property. Instances of active policy and activity types are considered in the model as entities that can be executed. We use the Execution Unit type for representing them as entities that go through a series of states at runtime. When an active policy is associated to one or several execution units, its rules verify whether each unit respects the implemented non-functional property by evaluating their conditions over their execution unit state, and when the property is not verified, the rules execute their actions for enforcing the property at runtime. We also proposed a proof of concept Active Policy Execution Engine for executing an active policy oriented workflow modelled using our AP Model. The engine implements an execution model that determines how AP, Rule and Activity instances interact among each other for adding non-functional properties (NFPs) to a workflow at execution time. We validated the AP Model and the Active Policy Execution Engine by defining active policy types for addressing exception handling, atomicity, state management, persistency and authentication properties. These active policy types were used for implementing reliable service oriented applications, and mashups for integrating data from services.Nous proposons une approche pour ajouter des propriétés non-fonctionnelles (traitement d'exceptions, atomicité, sécurité, persistance) à des coordinations de services. L'approche est basée sur un Modèle de Politiques Actives (AP Model) pour représenter les coordinations de services avec des propriétés non-fonctionnelles comme une collection de types. Dans notre modèle, une coordination de services est représentée comme un workflow compose d'un ensemble ordonné d'activité. Chaque activité est en charge d'implante un appel à l'opération d'un service. Nous utilisons le type Activité pour représenter le workflow et ses composants (c-à-d, les activités du workflow et l'ordre entre eux). Une propriété non-fonctionnelle est représentée comme un ou plusieurs types de politiques actives, chaque politique est compose d'un ensemble de règles événement-condition-action qui implantent un aspect d'un propriété. Les instances des entités du modèle, politique active et activité peuvent être exécutées. Nous utilisons le type unité d'exécution pour les représenter comme des entités dont l'exécution passe par des différents états d'exécution en exécution. Lorsqu'une politique active est associée à une ou plusieurs unités d'exécution, les règles vérifient si l'unité d'exécution respecte la propriété non-fonctionnelle implantée en évaluant leurs conditions sur leurs états d'exécution. Lorsqu'une propriété n'est pas vérifiée, les règles exécutant leurs actions pour renforcer les propriétés en cours d'exécution. Nous avons aussi proposé un Moteur d'exécution de politiques actives pour exécuter un workflow orientés politiques actives modélisé en utilisant notre AP Model. Le moteur implante un modèle d'exécution qui détermine comment les instances d'une AP, une règle et une activité interagissent entre elles pour ajouter des propriétés non-fonctionnelles (NFP) à un workflow en cours d'exécution. Nous avons validé le modèle AP et le moteur d'exécution de politiques actives en définissant des types de politiques actives pour adresser le traitement d'exceptions, l'atomicité, le traitement d'état, la persistance et l'authentification. Ces types de politiques actives ont été utilisés pour implanter des applications à base de services fiables, et pour intégrer les données fournies par des services à travers des mashups

    The use of TRAO to manage evolution risks in e-government

    Get PDF
    The need to develop and provide more efficient ways of providing Electronic Government Services to key stakeholders in government has brought about varying degrees of evolution in government. This evolution is seen in different ways like the merging of government departments, the merging of assets or its components with legacy assets etc. This has involved the incorporation of several practices that are geared towards the elimination of processes that are repetitive and manual while attempting to progressively encourage the interaction that exists between the different stakeholders. However, some of these practices have further complicated processes in government thus creating avenues for vulnerabilities which if exploited expose government and government assets to risks and threats. Focusing on ways to manage the issues accompanied with evolution can better prepare governments for manging the associated vulnerabilities, risks and threats. The basis of a conceptual framework is provided to establish the relationships that exist between the E-Government, asset and security domains. Thus, this thesis presents a design research project used in the management of evolution-related risks. The first part of the project focusses on the development of a generic ontology known as TRAO and a scenario ontology TRAOSc made up of different hypothetical scenarios. The resulting efficiency of the development of these ontologies have facilitated the development of an intelligent tool TRAOSearch that supports high-level semantically enriched queries. Results from the use of a case study prove that there are existing evolution-related issues which governments may not be fully prepared for. Furthermore, an ontological approach in the management of evolution-related risks showed that government stakeholders were interested in the use of intelligent processes that could improve government effectiveness while analysing the risks associated with doing this. Of more importance to this research was the ability to make inferences from the ontology on existing complex relationships that exist in the form of dependencies and interdependencies between Stakeholders and Assets. Thus, this thesis presents contributions in the aspect of advancing stakeholders understanding on the types of relationships that exist in government and the effect these relationships may have on service provisioning. Another novel contribution can be seen in the correction of the ambiguity associated with the terms Service, IT Service and E-Government. Furthermore, the feedback obtained from the use of an ontology-based tool during the evaluation phase of the project provides insights on whether governments must always be at par with technological evolution
    corecore