1. Planning the Reengineering of Legacy Systems, by Harry M. Sneed Reviewed by Odd Petter N. Slyngstad for DT8100, 27/1/2005

2. Overview Looks at the following aspects of re- engineering: –Cost-effectiveness –Preferability Provides a method to quantify costs & prove benefits of reengineering – as a method to improve existing software prod’s and proc’s

3. Planning overview 5-step procedure: –Project justification (increased quality, efficiency etc) –Portfolio analysis (prioritize candidate apps) –Cost estimation (include all sw components) –Cost-Benefit analysis (reengineering – maintenance cost + value increase) –Contracting (max level of distribution, avoid bottlenecks) (total planning estimated at 6 months)

4. Project justification Prove that it will reduce maintenance cost, improve quality by –Introducing a measurement program –Analyzing software quality –Analyzing maintenance costs –Assessing the software’s business value

5. Portfolio Analysis Plots applications in terms of business value and technical quality (ex: iso9126) Use chi-square chart (see article)

6. Cost Estimation Cost of the actual reengineering – must be lower than the benefits for specific projects...

7. Reengineering – definitions and objectives Business-process reengineering –Business process administration, supported by computer processes Data reengineering –Restructuring existing databases Software reengineering –Renovation of applications and software artifacts (map descriptions, job-control procedures, data structure views etc.) Recycling –Differs from reengineering in the sense that the result is a collection of reusable components, not a fully working system...

8. Cost-Benefit analysis Not just benefits of reengineering, also compare with benefits of redevelopment and....the benefits of doing nothing... And other factors such as unavailability, system lifetime, user satisfaction (the list goes on)... Example: A number of factors selected by UBS (annual maintenance, annual operations etc. etc. etc. see article for full list)

9. Contracting By time/material or by result (turnkey) Task definition –Derived from the list of objects needing reengineering (restructuring, conversion, testing, postdocumentation, system testing, configuration mgmt, system documentation etc.) Effort distribution –Recommendations on how and where to carry out the actual work (testing effort, component reengineering etc.)

10. Summary ”Reengineering is NOT easy to sell” Must be justified not only with technical concerns, but also with business issues. Questions, comments ??