Formal Identification of Right-Grained Services for Service-Oriented Modeling

Abstract. Identifying the right-grained services is important to lead the successful service orientation because it has a direct impact on two major goals: the composability of loosely-coupled services, and the reusability of individual services in different contexts. Although the concept of service orientation has been intensively debated in recent years, a unified methodic approach for identifying services has not yet been reached. In this paper, we suggest a formal approach to identify services at the right level of granularity from the business process model. Our approach uses the concept of graph clustering and provides a systematical approach by defining the cost metric as a measure of the interaction costs. To effectively extract service information from the business model, we take activities as the smallest units in service identification and cluster activities with high interaction cost into a task through hierarchical clustering algorithm, so as to reduce the coupling of remote tasks and to increase local task cohesion

Pilot Implementation: Learning from Field Tests in IS Development

A recurrent problem in information-systems development (ISD) is that many design shortcomings are not detected during development, but first after the system has been delivered and implemented in its intended environment. Pilot implementations appear to promise a way to extend prototyping from the laboratory to the field, thereby allowing users to experience a system design under realistic conditions and developers to get feedback from realistic use while the design is still malleable. We characterize pilot implementation, contrast it with prototyping, propose a five-element model of pilot implementation and provide three empirical illustrations of our model. We conclude that pilot implementation has much merit as an ISD technique when system performance is contingent on context. But we also warn developers that, despite their seductive conceptual simplicity, pilot implementations can be difficult to plan and conduct. It is sometimes assumed that pilot implementations are less complicated and risky than ordinary implementations. Pilot implementations are, however, neither prototyping nor small-scale versions of full-scale implementations; they are fundamentally different and have their own challenges, which will be enumerated and discussed in this article