Background
Nowadays, as the Internet has become the main platform on which enterprises carry out businesses globally, the environment of enterprise applications will be characterized by frequently changing market demands, time-to-market pressure and fierce competition. Therefore, it requires that the enterprise business systems should provide more flexibility than present-day systems can afford. The key to tackle this challenge completely is to utilize a kind of novel software system architecture which is required to be distributed, loose-coupled and reconfigurable. Fortunately, these requirements can be best addressed by Service-oriented Architecture (SOA).
SOA is an architectural style whose goal is to achieve loose coupling among interacting services and to build software systems by composing services (Papazoglou & Georgakopoulos, 2003). It provides greater flexibility and agility while allowing business systems to use heterogeneous resources efficiently and effectively. Web services technology has been regarded as the preferred implementation vehicle for SOA. A Web service is a software entity that supports interoperable application-to-application interaction over Internet. At present, the accelerating creation and use of Web Services in enterprises informatics is a major trend (Kalogeras, Gialelis et al., 2006). Thus, more and more Web services are published in Internet by enterprises to accelerate the cooperation with their partners. For example, in the scenario of supply chain management, a manufacturer receives an order to deliver some merchandise to a retailer. In order to accomplish this business, the manufacture finds possible suppliers and selects the best available service provided by one supplier. However, due to the highly distributed and dynamic environment, Web services may be located at different enterprises and come and leave at any time without prior warning. In that context, no one is likely to have the detailed knowledge of all Web services in advance. As a result, one of great challenges is how to discover the suitable Web services accurately and quickly. Thus, service discovery, which aims at retrieving services advertised in a repository that match a user’s goal, has allured much attention both from industry and academy.