Determining granularity of independent tasks for reengineering a legacy system into an OO system

Reengineering a COBOL legacy system is a difficult multi-step process, particularly when the COBOL legacy system is a sequential procedural-driven system which is being reengineered into an object oriented, event-driven system. In this scenario, it is necessary to analyse the legacy system in order to identify which tasks can be executed independently and which tasks must be executed sequentially. The focus of reengineering is too often based on theory rather than based on experience gained from real-world examples. This paper hopes to address this imbalance by providing a practical application of reengineering to an actual legacy telecommunications system.