Most large organizations have legacy applications based on older technologies that are now expensive to maintain and difficult to integrate with transactions that occur in a modern web-oriented environment.
In addition, the human resources required to support these applications are increasingly difficult to obtain. Although it is not hard to learn Cobol, programmers with knowledge of systems software such as JES, VTAM, RACF, IMS, CICS, and IDMS, operating systems such as MCP, MPE, VME, VSE, OS/390, and MVS, and older databases such as Adabas are hard to find.
On the other hand, if your organization has maintained its legacy applications, it has a tremendous investment in software that contains business rules and decision functions that correspond to its needs and current practices.
To justify legacy modernization, you need to demonstrate how modernization will increase future revenue. Therefore, you need a modernization strategy that maximizes the value of your investment in existing legacy applications, reduces maintenance costs, and produces applications with equivalent functionality that can easily be enhanced to accommodate future needs.
Organizations can take different paths to modernize their legacy applications.
If you need an application with only standard functionality, you may find a COTS (Commercial Off-The-Shelf) application that provides it. This can be a fast and easy solution for start-ups and organizations that do not have legacy applications whose functionality needs to be duplicated. However, COTS software is usually difficult and expensive to modify with the result that organizations are often forced to modify their procedures to satisfy the requirements of their off-the-shelf software.
If a legacy application no longer meets business needs and the cost of simultaneously modernizing and enhancing it is very high, you can do a complete re-write. However, manually rewriting an application from scratch is always the most time-consuming and usually the most costly and most risky option.
Modernizing existing mainframe applications by renovating current application assets has become an accepted practice that has proved its worth. Legacy modernization leverages existing application assets and enhances them by incorporating modern technologies. There is no need to redefine processes that have remained unchanged just because technology has advanced. Legacy renovation preserves the organization's past investment, reduces the risk of cost overruns, and increases the likelihood that the project will be completed on time.
MOST Technologies uses automatic tools for converting legacy applications from languages such as Natural, Cobol, PL/1, Fortran and Assembler to newer languages including Java. MOST’s modernization suite includes utilities that automate data migration from older databases such as Adabas to newer Relational Database Management Systems with fully normalized schemas. MOST also has tools that automatically re-engineer applications into a 3-layer Presentation, Business and Data Access architecture to ensure that the converted code can be easily maintained and enhanced.
For more information about the modernization decision process, see
Modernization – Clearing a Pathway to Success published by the Standish Group at http://www.semanticdesigns.com/Products/Services/StandishGroupModernizationWhitePaper2011.pdf