Abstract:

Web Services have experienced great interest during the last years as they are expected to act as enablers of seamless application-to-application integration both within company boundaries and on a global scale. Especially the automation of cross-organizational, information intensive business processes through the loose composition of standardized services is believed to significantly reduce costs and increase operational agility. In this work, we present three different strategies to supporting Web Service composition across corporate boundaries: A central service orchestration architecture, a hybrid orchestration approach with hub support and finally a fully decentralized orchestration solution without any central control entity. We evaluate and compare the three strategies on the basis of the eight criteria functional scope, monitoring capabilities, fault detection and removal, simultaneousness of process instance execution, scalability, security, seamless interoperability of the coupled applications as well as end-point complexity. The analysis shows that the hybrid approach represents the most promising solution as it unifies the advantages of centralized and decentralized strategies.