Ever since the first vacuum tube burned out in the first commercial digital computer, calls for IT modernization have targeted older, legacy systems. Over the years, one plan after another for retiring increasingly aged mainframes, midrange systems, databases, and enterprise applications have crossed many a CIOs desk.
Yet while finally chucking that old system and replacing it with new and shiny tech may sound appealing, in practice such full-fledged migrations are rarely practical or cost-effective. Instead, many enterprises are realizing that older systems still provide value. Thus legacy modernization strategies are better off focusing on coexistence rather than all-out migration.
However, every organization’s legacy context is different, as are its business goals. As a result, there are a plethora of migration, modernization, and coexistence scenarios, each with its own pros and cons. IT leaders must now understand the breadth of options open to them in order to make the right decisions about how to deal with legacy systems and applications.
Multiple Migration and Modernization Scenarios
Fortunately, legacy migration and modernization strategies have come a long way since the days of vacuum tubes. The 2000s brought Service-Oriented Architecture (SOA) to the table, helping organizations abstract legacy assets as Web Services. Today, the evolving notion of SOA has given rise to modern Application Programming Interfaces (APIs).
Understanding the modern challenge of coexistence, therefore, depends upon properly learning the lessons of SOA and APIs. While SOA was a mixed success, it unquestionably moved the modernization ball forward. Not all migration and modernization scenarios take advantage of SOA lessons learned, however. To illustrate these challenges, this paper breaks down such challenges into six basic scenarios.
The illustrations below are simplified representations of each scenario, as the real world context is inevitably more complicated. Nevertheless, most migration and modernization scenarios tend to follow one or more of the following patterns.
The ‘lipstick on the pig’ scenario
The first two scenarios are dangerous oversimplifications – common failure scenarios that don’t adequately address the complexities of modernizing a legacy environment.
Download the entire white paper at https://intellyx.com/wp-content/uploads/2015/12/Legacy-Migration-vs.-Modernization-The-Challenge-of-Coexistence.pdf.
OpenLegacy is an Intellyx client. Intellyx retains full editorial control over the content of this white paper.
