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In general, Policy-based approaches play an important role in the management of web services, for instance, in the choice of semantic web service and quality of services (QoS) in particular. The present research work illustrates a procedure for the web service selection among functionality similar web services based on WS-Policy semantic matching. In this study, the procedure of WS-Policy publishing in the UDDI registry was also described. The approach, which is used to represent the policies, is thus represented as semantic trees, and in this representation, measurable quality attributes are considered; and the certain matching operations are used to identify the similarity match via match function or similarity distance function. The illustration of semantic concepts and rules during policy matching, which is not possible by using a mere semantic concept, leads to better web service matches. The proposed approach has been validated through various tests that can evaluate the similarity of large and arbitrary sets of measurable quality attributes. We also compared the proposed procedure with the other ones. The proposed procedure for web service choose, which uses WS-Policy semantic matching, can be more effective to solve different problems like selection, composition, and substitution of services.

Composite web services are a group of web services which together offer service functionality. Faults can occur during composition or execution of any of the services that make up the composite services. Run-time monitoring of web service execution enables real-time detection of faults concurrent with the service execution. This paper extends our previous work on fault detection of single web services to detect faults in composite web services. Fault handler has been proposed to detect faults during composition of web services for static, semi dynamic and dynamic compositions. Policies have been used to denote the intended run-time behavior of web services. Web service execution has been monitored against these policies to detect run-time faults. The proposed work has been tested using a sample web service application and the results are presented. [ABSTRACT FROM AUTHOR]

A systematic way for treating non-functional (quality) attributes into the business process management lifecycle is still a challenge. The agnostic, integrated and automated treatment of these attributes from the most abstract business level to their technical realisation at execution level is a complex task. In this context, this paper presents a model-driven approach centred on quality attributes of business processes. Additionally, two key characteristics of our approach are the agnostic treatment of the quality attribute being considered and its projection on standards such as user requirement notation (URN), UML for QoS and WS-Policy. To illustrate the proposed approach, a supply chain management use case is used. Finally, in order to evaluate the model-driven approach, an evaluation plan based on goal/question/metric (GQM) is defined, providing the rationale to define and to apply evaluation metrics of interest. [ABSTRACT FROM AUTHOR]

Web services provide distributed communication in a platform independent way. The WS-* standards define how middleware aspects (security, reliability, transactions, etc.) can be realized through web services. Although the WS-Policy standard family can be used to configure the various WS-* protocols, they are very hard to construct and to maintain manually. In addition, most SOA products and Grid systems implementing these standards provide their own methods for configuring these protocols, making it very difficult to match the various configuration options of different products. This fact inspired us to propose a platform independent metamodel for describing distributed systems of web services including the most important WS-* standards. The present article defines the full metamodel, it specifies the corresponding programming language formally, and it shows the productivity of the framework built around the metamodel through real-life examples. The framework is capable of generating product specific configuration files and source codes, resulting in directly interoperable applications even between different SOA products. The framework could also promote interoperability with Grid systems built on WS-* protocols. [ABSTRACT FROM AUTHOR]

Abstract: In the last years, the need for integrating QoS to service oriented architecture has become a significant factor for managing service-based systems. In addition, combining self-* and policy-based management has major advantages since it reduces complexity management and effectively drives self-adaptation of Web services. Current service oriented architecture does not support policy-based self-management. To allow this, the description of autonomic Web services (AWS) must not be limited to functional and non-functional data. Indeed, QoS data are not sufficient to effectively drive the self-adaptation process. In addition, providers must participate in the self-adaptation process as they are aware of the capabilities and requirements of their published services and the exceptions that may occur. In this paper, we propose a rich information model that allows describing autonomic Web services based not only on QoS data but also on additional information such as service specific adaptation actions. We extend WS-Policy to specify services related data. UDDI is also extended to support policy-based self-management. [Copyright &y& Elsevier]

The dynamic integration of autonomous, clustered and heterogeneous networked components are dynamically integrated for effective resource utilization of computing resources. This paper proposes a mechanism for expressing resource usage policies in computational grid for heterogeneous device with varying resource request. It extends the WS-Policy specification to represent grid resource policy requirements and implements APIs to compare and negotiate the usage policies. It also enhances the usage policy matching by using the concept of ontology. Grid resource usage policy ontology is proposed to support semantic based matching of resource usage policy against the user's requirements. This semantic based grid resource usage policy mechanism is then integrated with Gridway meta-scheduler to implement the resource selection based on the capability matching as well as usage policy matching in the grid environment. [ABSTRACT FROM AUTHOR]

A Web service is defined as an autonomous unit of application logic that provides either some business functionality or information to other applications through an Internet connection. Web services are based on a set of XML standards such as Simple Object Access Protocol (SOAP), Universal Description, Discovery and Integration (UDDI) and Web Services Description Language (WSDL). The benefits of adopting Web services over traditional business-to-business applications include faster time to production, convergence of disparate business functionalities, a significant reduction in total cost of development, and easy to deploy business applications for trading partners. However, Web services architectures are built on an insecure, unmonitored and shared environment, which is open to events such as security threats. Security concerns are the major barrier that prevents many business organisations from implementing or employing Web services. This paper discusses one of the classical security policies that deal with Conflict of Interest (CIR) - the Chinese wall security policy. The paper then extends this concept into specifying and implementing conflict of interest assertions in the newly developed WS-Policy. WS-Policy is an XML representation that provides a grammar for expressing Web services policies, to allow service locators to have a common interpretation of security requirements in the matchmaking process. In addition, this paper also discusses the concept of Separation of Duties (SOD) and its relationships with CIR in the context of matchmaking process. The paper will conclude with a prototype framework with "CIRService" and "SoDService" services for matchmaking process. [ABSTRACT FROM AUTHOR]

Web services are increasingly being provided and consumed in and between cloud environments. Learn how to leverage various interoperable standards to address security challenges in a cloud or distributed Web services architecture. [ABSTRACT FROM PUBLISHER]