Information is the lifeblood of any organisation. However, in most companies, data and the rules about data that are embedded in applications, databases and other systems are opaque. Typically these are in multiple places and often in legacy environments. Moreover, the data is not isolated. It does not exist in a single place but across a heterogeneous landscape. This creates difficulties whenever you introduce a new application, modernise an existing one or migrate from an older system, because you need to preserve the integrity of the data and its relationships and rules, not just within the application or database under consideration but across all of the systems that share that data or part of that data.
Given this complexity, what sort of technology do you need in order to ensure that developments, whether new or for replacement purposes, do not disrupt your existing environment? Moreover, how can you do that as quickly and efficiently as possible, at a minimal cost? These are the questions that this paper seeks to answer. In order to investigate them we will first need to consider the extent of the problem, which will require something of a history lesson, and then we will discuss the sort of technical requirements needed to resolve the issues under discussion. What we will find is that there are different technical requirements depending upon where you are starting from and where you want to get to, but we would posit that it makes sense to use an approach that covers all eventualities. Finally, we will investigate the products of one company, REVER, and see how they match to the requirements we have identified.