Semantic-Based Web Services Integration

With more and more applications of web service, the automatic web services integration (including discovery and composition) are becoming the focus of research. The description mechanism of web services information is important for the veracity and automation extent of discovering and composing web services. Traditionally, most web services are described with WSDL on their physical information, including little semantic information in service registration, so the agent which performs the services integration does not have enough information to deal with the concepts mapping of different fields, and the participation of human being is often required. The Ontology concept is put forward to solves the problem of concepts mapping between multi-fields to a great extent, some knowledge representation languages based on ontology provide good logic restriction, all of these are helpful for agents to grasp the concepts in reality.DAML-S is the specification especially established to describe the web services ontology. With the basic ontology, it can establish the framework for services description and sharing. By this, web stations can declare and describe the provided services using some basic classes and properties. Once agents can understand the service description, web services can achieve the highly automated self-composition and computation.This paper, based on an in-depth research on related work, finds that the establishment of precise web service semantic description mechanism is the key to solve the problem, and combines WSDL with DAML-S to form the extended web service semantic description model. To overcome the shortcoming in traditional web service registration, semantic processing layer is added to bring the semantic information of registered web services to maturity, also the method of how to organize the registered web services for the registration center is set forth to facilitate services discovery in UDDI. Further more, this paper proposes an improved approach to web services composition based on weight directed graph. In this approach, we describe not only the mapping of services parameters in detail, but also choose a different algorithm from the one in the existing literature according to the actual situation, to promote the efficiency.