Abstract. The current standards for web service composition, e.g. BPEL. neither cater for dynamic service composition nor for dynamic business configuration. Our firm belief is that business processes can be built dynamically by composing web services in a model driven fashion where the design process is controlled and governed by a series of business rules. In this paper we examine the functional requirements of service composition and introduce a phased approach to the development of service compositions that spans abstract definition, scheduling, construction and execution. Subsequently, we analyze the information requirements for developing service compositions by identifying the basic elements in a web service composition and the business rules that are used to govern the development of service compositions. 1

Abstract. One of the assumptions all the standards for web service composition (e.g. BPEL) make is that the business process is pre-defined. Obviously this assumption does not hold if business needs to accommodate changes in applications, technology, and organizational policies. We believe business processes can be dynamically built by composing web services if they are constructed based on and governed by business rules. In this paper we first analyze the basic elements in web service composition. Then we present a rule driven mechanism to govern and guide the process of service composition in terms of five broad composition phases spanning abstract definition, scheduling, construction, execution, and evolution to support on demand and on the fly business process generation. 1

Abstract. With web services emerging as a promising technology for supporting open and dynamic business processes, it is witnessed that standards for business process specification in the context of web services composition have been fast developed in recent years, e.g. WSFL, XLang, BPEL. However, none of the proposing specifications really address the issues of dynamic business process creation, e.g. a vast service space to search, a variety of services to compare and match, and different ways to construct business processes. One of the assumptions these standards make is that the business process is pre-defined. Obviously this assumption does not hold if the business needs to accommodate changes in applications, technology, and organizational policies. We believe business processes can be dynamically built by composing web services if they are constructed based on and governed by business rules. In this paper we analyze the basic elements in business modelling and how they relate to the web service composition process. As a result a rule driven mechanism is developed to govern and guide the process of service composition definition, scheduling, construction, execution, and evolution to support on demand and on the fly business process building. 1