Interactive composition of WSMO based semantic web services in IRS-III

The discovery and integration of services in a composition are challenging tasks due to the lack of semantic in the Web services' description. WSMO community is working on developing ontologies and infrastructures to support Semantic Web Services. In this paper, we present a tool that takes into account WSMO descriptions to support a user guided, interactive composition approach whereby Web services are discovered and recommended to the users according to the composition context. The generated composition is orchestrated in IRS-III by our Java API for dataflow orchestration

Context and semantic composition of Web services

Composition of Web services is a cornerstone step in the development of interoperable systems. However, Web services still face data-heterogeneity challenges, although several attempts of using semantics. In addition, the context in which Web services evolve is still somehow ignored , hampering their adaptability to changes in composition situations. In this paper, we argue how context permits to determine the semantics of interfaces that Web services expose to third parties. We show the need for a context- and semantic-based approach for Web services composition. © Springer-Verlag Berlin Heidelberg 2006

Towards a semantic- and context-based approach for composing web services

Despite the widespread adoption of web services, several obstacles still hinder their smooth automatic composition. First, techniques that exploit semantic information during web services discovery are still lagging behind despite multiple initiatives like OWL-S. Second, the context in which web services evolve is, to a certain extent, ignored. This prevents deploying adaptable web services. In this paper, we propose a semantic- and context-based approach for web services composition. By semantics, we mean the capacity of web services, which are engaged in interactions, to understand what these interactions are about and how to carry out these interactions. By context, we mean the capacity of web services to assess their current capabilities and ongoing commitments before these services participate in any composition. © 2005 Inderscience Enterprises Ltd

Semantic web service composition in IRS-III: The structured approach

Semantic Web Services facilitate activities including automatic discovery and composition of Web Services. Research initiatives such as WSMO have been developing specifications for this technology. This paper describes a model for composition of Web services. The proposed model complements the WSMO orchestration in IRS-III, a framework for Semantic Web Services based on WSMO specification. We present a tool based on the above model that supports a user-guided interactive composition approach, by recommending component Web services according to the composition context

What can context do for web services?

Academia and industry, with the rapid development of information technologies, are adopting Web services due to their integration capabilities. Web services are being actively used for connecting business processes in business-to-business scenarios. The Web services community uses different languages for specifying Web services composition like BPEL and WSFL. The primary objective of these specification languages is to provide a high-level description of the composition process independent from any implementation details or concern. The need for a common semantics is intensified when Web services participate in the same composition. Web services, to reduce the limitations, must be context-aware, context is the information which characterizes the interactions between humans, applications and the environment. A possible solution to achieving a contextual semantic composition of Web services is built upon the semantic-value concept

Semantic Service Description Framework for Efficient Service Discovery and Composition

Web services have been widely adopted as a new distributed system technology by industries in the areas of, enterprise application integration, business process management, and virtual organisation. However, lack of semantics in current Web services standards has been a major barrier in the further improvement of service discovery and composition. For the last decade, Semantic Web Services have become an important research topic to enrich the semantics of Web services. The key objective of Semantic Web Services is to achieve automatic/semi-automatic Web service discovery, invocation, and composition. There are several existing semantic Web service description frameworks, such as, OWL-S, WSDL-S, and WSMF. However, existing frameworks have several issues, such as insufficient service usage context information, precisely specified requirements needed to locate services, lacking information about inter-service relationships, and insufficient/incomplete information handling, make the process of service discovery and composition not as efficient as it should be. To address these problems, a context-based semantic service description framework is proposed in this thesis. This framework focuses on not only capabilities of Web services, but also the usage context information of Web services, which we consider as an important factor in efficient service discovery and composition. Based on this framework, an enhanced service discovery mechanism is proposed. It gives service users more flexibility to search for services in more natural ways rather than only by technical specifications of required services. The service discovery mechanism also demonstrates how the features provided by the framework can facilitate the service discovery and composition processes. Together with the framework, a transformation method is provided to transform exiting service descriptions into the new framework based descriptions. The framework is evaluated through a scenario based analysis in comparison with OWL-S and a prototype based performance evaluation in terms of query response time, the precision and recall ratio, and system scalability

SEKE - Towards Context-based Mediation for Semantic Web Services Composition

Web services composition is a keystone towards the development of interoperable systems. However, desp; ite several efforts for explicit semantic description, Web services still face data-heterogeneity chal; lenges. Correct interpretation of data exchanged between composed Web services is hampered by differen; t implicit modeling assumptions and representations. In this paper, we demonstrate the importance of c; ontext to facilitate data exchange, and describe a context representation model for Web services. Then; , we present a context-based mediation architecture that helps performing meaningful composition

Context constraint integration and validation in dynamic web service compositions

System architectures that cross organisational boundaries are usually implemented based on Web service technologies due to their inherent interoperability benets. With increasing exibility requirements, such as on-demand service provision, a dynamic approach to service architecture focussing on composition at runtime is needed. The possibility of technical faults, but also violations of functional and semantic constraints require a comprehensive notion of context that captures composition-relevant aspects. Context-aware techniques are consequently required to support constraint validation for dynamic service composition. We present techniques to respond to problems occurring during the execution of dynamically composed Web services implemented in WS-BPEL. A notion of context { covering physical and contractual faults and violations { is used to safeguard composed service executions dynamically. Our aim is to present an architectural framework from an application-oriented perspective, addressing practical considerations of a technical framework