From run-time behavior to usage scenarios

A key challenge facing IT organizations today is their evolution towards adopting e-business practices that gives rise to the need for reengineering their underlying systems. Any reengineering effort has to be aware of the functional requirements of the subject system, in order not to violate the integrity of its intended uses. However, as systems get regularly maintained throughout their lifecycle, the documentation of their requirements often become obsolete or get lost. To address this problem of software requirements loss, we have developed an interaction-pattern mining method for the recovery of functional requirements as usage scenarios. Our method analyzes traces of the run-time system-user interaction to discover frequently recurring patterns; these patterns correspond to the functionality currently exercised by the system users, represented as usage scenarios. The discovered scenarios provide the basis for reengineering the system into web-accessible components, each one supporting one of the discovered scenarios. In this paper, we describe IPM2, our interaction-pattern discovery algorithm, we illustrate it with a case study from a real application and we give an overview of the reengineering process in the context of which it is employed.