The World Wide Web is emerging not only as an infrastructure for data, but also for a broader variety of resources that are increasingly being made available as Web services. Relevant current standards like UDDI, WSDL, and SOAP are in their fledgling years and form the basis of making Web services a workable and broadly adopted technology. However, realizing the fuller scope of the promise of Web services and associated service oriented architecture will requite further technological advances in the areas of service interoperation, service discovery, service composition, and process orchestration. Semantics, especially as supported by the use of ontologies, and related Semantic Web technologies, are likely to provide better qualitative and scalable solutions to these requirements. Just as semantic annotation of data in the Semantic Web is the first critical step to better search, integration and analytics over heterogeneous data, semantic annotation of Web services is an equally critical first step to achieving the above promise. Our approach is to work with existing Web services technologies and combine them with ideas from the Semantic Web to create a better framework for Web service discovery and composition. In this paper we present MWSAF (METEOR-S Web Service Annotation Framework), a framework for semi-automatically marking up Web service descriptions with ontologies. We have developed algorithms to match and annotate WSDL files with relevant ontologies. We use domain ontologies to categorize Web services into domains. An empirical study of our approach is presented to help evaluate its performance.

The ability to rapidly locate useful on-line services (e.g. software applications, software components, process models, or service organizations), as opposed to simply useful documents, is becoming increasingly critical in many domains. Current service retrieval technology is, however, notoriously prone to low precision. This paper describes a novel service retrieval approached based on the sophisticated use of process ontologies. Our preliminary evaluations suggest that this approach offers qualitatively higher retrieval precision than existing (keyword and tablebased) approaches without sacrificing recall and computational tractability/scalability.

Web services have a potential to enhance B2B ecommerce over the Internet by allowing companies and organizations to publish their business processes on service directories where potential trading partners can find them. This can give rise to new business paradigms based on ad-hoc trading relations as companies, particularly small to medium scale, can cheaply and flexibly enter into fruitful contracts, e.g., through subcontracting from big companies by simply publishing their business processes and the services they offer. More business process support by the web service infrastructure is however needed before such a paradigm change can materialize. A service for searching and matchmaking of business processes does not yet exist in the current infrastructure. We believe that such a service is needed and will enable companies and organizations to be able to establish ad-hoc business relations without relying on manually negotiated interorganizational workflows. This paper gives a formal semantics to business process matchmaking based on finite state automata extended by logical expressions associated to states. 1.

Abstract. Web Services are emerging technologies that enable applicationto-application communication and reuse of autonomous services over Web. Traditional Workflow Management Systems fail to provide a comprehensive solution for a Web Service based Workflow. A framework that meets the quality of service (QoS) requirements for ad hoc Internet based Services is rarely provided. Considering the increasing demand for expanding services and application requirements coupled with use of Web Services, it is a challenging task to develop a QoS model as a framework for Web Service based Workflows. In this paper, we have proposed a QoS oriented Framework, called WebQ, that is capable of conducting the adaptive selection process and simultaneously provides binding and execution of Web Services for the underlying workflow. To achieve these objectives, as the first step, we have designed a QoS model for Web Service selection, binding, and execution. We, then, develop a set of algorithms to compute QoS parameters and implement them using a rule-based system. A series of experiments performed on workflows composed of real Web Services have confirmed that the proposed framework is very effective in improving the overall QoS of the system. 1

To achieve the dream of the semantic web, it must be possible for ordinary users to invoke services. Exactly how to turn this dream into reality is a challenging opportunity and an interesting research problem. It is clear that users need simple-to-invoke-and-use services. This paper shows that an approach strongly based on conceptual modeling can meet this challenge for a particular type of service—those that involve establishing an agreed-upon relationship, such as making an appointment, setting up a meeting, selling and purchasing products, establishing employee job assignments, and many more. For these services, users can specify their requests as free-form text and then interact with the system in a simple way to complete the specification of a service request, if necessary, and invoke the service. Behind the scenes, the system uses a conceptual-model-based information extraction ontology to (1) recognize the request and match it with an appropriate ontology, (2) discover and obtain missing information, and (3) establish agreed-upon, conceptual-model-constrained relationships with respect to the desired service. The paper lays out our vision for this type of semantic web service, gives the status of our prototype implementation, and explains how and why it works.

Abstract. Proliferation of Web technologies and the ubiquitous Internet has resulted in a tremendous increase in the need to deliver one-stop Web services, which are often composed of multiple component services that cross organizational boundaries. It is essential that these Web services, referred to in this paper as service flows, be carefully composed in a dynamic and customized manner to suit to the changing needs of the customers. This composition should be conducted in such a manner that (i) the composed service flow adheres to the policies imposed by the organizations offering the component services, (ii) the selected component services are compatible with one another so that the entire composition would result in a successful service flow, and (iii) the selected component services most closely meet the customer requirements. In this paper, we propose a policy-based Web service composition that utilizes the semantics associated with the component services. We consider policies imposed by different entities while composing service flows, which include service policies (imposed by the organizations offering component services), service flow policies (associated with the entire service flow), and user policies (the user requirements expressed as policies). In addition to these policies, one may consider rules at the syntactic and semantic levels that can be used to select relevant component services in order to compose customized service flows, by considering the notions of syntactic, semantic and policy compatibility. We model the different policies and the service topic ontology using OWL, DAML-S, RuleML and RDF standards.

Abstract. Recently, Web services have generated great interests in both vendors and researchers. Web services, based on existing Internet protocols and open standards, can provide a flexible solution to the problem of application integration. With the help of WSDL, SOAP, and UDDI, Web services are becoming popular in Web applications. However, the current Web services architectures are confronted with a few stubborn problems, for instance, security. In this paper, we shall give an overview of these problems. We believe that solving these problems will become crucial to success of Web services. In the end, we predict distinct advances in semantic Grid services.

Abstract. The ability of agents and services to automatically locate and interact with unknown partners is a goal for both the semantic web and web services. This, “serendipitous interoperability”, is hindered by the lack of an explicit means of describing what services (or agents) are able to do, that is, their capabilities. At present, informal descriptions of what services can do are found in “documentation ” elements; or they are somehow encoded in operation names and signatures. We show, by reference to existing service examples, how ambiguous and imprecise capability descriptions hamper the attainment of automated interoperability goals in the open, global web environment. In this paper we propose a structured, machine readable description of capabilities, which may help to increase the recall and precision of service discovery mechanisms. Our capability description draws on previous work in capability and process modeling and allows the incorporation of external classification schemes. The capability description is presented as a conceptual meta model. The model supports conceptual queries and can be used as an extension to the DAML-S Service Profile. 1

Abstract: Service discovery of state-dependent services has to take workflow aspects into account. To increase the usability of a query result, the results should be ordered with regard to their relevance, that is, the similarity of the query and the result list entry. Although there exist service discovery solutions considering workflow aspects, there is no support of ordering the result list. However, there exist several similarity measures in different research areas, which are applied in this paper to workflow similarity based on Finite State Automata. 1

Abstract. A methodology provides description of process and guidance for producing ontology that facilitates management of the enterprise engineering products. Method support in terms of detailed guidelines is important to ensure the quality of ontologies. Then, it is also important to be able to evaluate the quality of such method guidelines. This paper proposes an analytical framework for such evaluations, achieved by combining Uschold’s unified methodology for ontology building with a semiotic framework for understanding quality in conceptual modelling. These two frameworks are shown to map well onto each other, and indicates a potential in applying the semiotic framework not merely in evaluation and choice of methodology for ontology building, but also in embodying quality throughout the process of ontology building. 1