The reengineering of the enterprise, in this case, may require the replacement of all or most of the batch-oriented systems. A detailed understanding of the internal structure of the legacy systems does not make economic sense in order to move forward. Sometimes a combination of different activities is called for. In fact, a combination strategy is often the soundest and most cost-effective approach. This is a holistic approach to a disciplined evolution of systems, which addresses each part of the whole system in the appropriate way.
Careful analysis is required on several fronts.
Only after these questions are answered can a plan be developed for the maintenance, restoration, or creation of the good health for a legacy system. We then give some specific examples of that technology and provide case studies of how the technology is being used in practice. The examples have been chosen to provide evidence for the conjecture that the relative cost and practicality of wrapping favors its use compared to deep understanding.