Flexible Coordination of E-Services

Information systems are increasingly being built using e-services invoked across the internet. Businesses can create a virtual application by composing simpler existing e-services provided by a number of different service providers. These composed e-services, or e-workflows, must operate in a highly fluid environment, where new services become available for use and business practices are subject to frequent change. This imposes demanding requirements for flexibility on the workflow system that manages the business process. In this paper we describe our efforts to extend workflow orchestration by incorporating information workers in process enactment, to enable both system and users to cooperate in interpreting the process model. This allows for a variety of methods for simple e-services to be interconnected and composed into more complex e-services. This approach also provides an elegant way to incorporate ad hoc changes or specialization during workflow enactment and to react to exceptions. We are building a prototype of our workflow adaptation services on top of a commercial workflow orchestration engine.