Redesign, restructuring and rejuvenation of legacy applications

“In the major banks the production and corrective maintenance costs are about 70 to 75 % of the IT budget; 6 to 10 % of additional costs are necessary for the developments implied by regulatory conformance problems (IAS-IFRS, BASEL II); thus the budget for really new developments is limited to a small proportion of 15 to 20 %.”

Results of a recent study, conducted by the BOSTON Group

Component Based Development (CBD) is particularly suited to creating new applications. So it is obvious that other solutions must be considered to handle what appears to be the major problems of the IT managers in large companies, according to the statistics of the BOSTON Group : the maintenance, the restructuring and the integration of the applications that sometimes have been in use for a long while. This problem is often known as “legacy rejuvenation”.

There are a certain number of valid arguments for considering this type of rejuvenation :

  • The present system is completely outdated, considering the current requirements.
  • Substantial cost reductions are possible when replacing the old legacy programs by a more modern and less expensive system (Linux may be a valid example).
  • High productivity gains can be achieved in the daily work, while tightly integrating the various existing applications in an overall organisation, especially if these applications were initially developed for specific departments of the organisation.
  • Certain program modifications may be mandatory, due to regulatory constraints. In the banking domain this is particularly true, when introducing the new accounting systems or the BASEL II regulations.
  • Customers as well as suppliers in certain circumstances, may wish for a better service by an online access to various information, generally using an Internet link.
  • It is vitally important that existing applications should be able to react quickly to all the changes and modifications that occur at a fast rate during the daily lifecycle.
  • Information technology must be inline with the company strategy, using agile methods and promoting innovation, which is rarely the case with legacy applications.

The methods and tools that have been defined and implemented over the years by CompoSys allow us to consider this complex problem of rejuvenating existing applications, wholly or partially, according to clearly defined plans. We do not intend to reinvent the wheel, which seriously reduces the associated risks. According to the customers needs, various approaches are possible, but all these approaches will be based on agile and incremental methodologies; the “big bang” will never be considered by CompoSys as a serious possibility for rejuvenating.

Integrating existing applications in a Service Oriented Architecture (SOA) is always a valid scheme. Where the outdated legacy applications have been written in COBOL, which is very often the case, it is also possible to rejuvenate them by rewriting the programs in another modern language, by using more or less automated methodologies and tools.