Using Dr Koskinen approach to decision making can help support this business case.
1) Continue to use/maintain the current software by modernizing it (baby steps first)
2) Replacement a) try to find a solution ou there
b) complete rewrite of the system
Rewrite is estimated à 160,000 hours of effort. After discussions the decision is to salvage the existing system. Strategy will be to migrate to newer technology and refactor worst parts. Scalability is also an issue. I propose to go with 'cloud computing' backend. Looking at the system there are currently enough information to pass from C+ to C#. A small pilot done this week shows that the effort will be around 6,500 hours to convert. Only 8% of the system requires refactoring. This will take 3,000 hours to do and includes the migration of the obsolete Borland database to a more recent (and scalable) technology can easily be achieved.
Parallel run is mandatory so existing Dabatase + stubs will be used in parallel with new database. I'm out of there and preparing the new software maintenance course at the University starting in September.
