In the context of computing, the term legacy system refers to computer systems, software, programming language, application programs or any other technology that is either out of date, obsolete or might be still in use because its application programs cannot be upgraded. Sometimes the legacy system can be used as a disparaging term for technology that is still up-to-date but he data cannot be converted into newer or standard formats.
These are usually software systems developed for an organization, years back using technologies that are now obsolete. Since these systems remain to be business critical even on the present date, they have been given the name legacy systems.
More than simple software systems, legacy systems can be considered to be socio-technical systems. The way in which legacy systems are mostly structured is as follows:
Legacy systems can be categorized according to their limitations of usage, as:
Legacy systems generally use obsolete Data Base Management Systems (DBMS) which in most cases are incompatible with the other DBMSs used by the organization. To transform into an entirely new database and mainframe the organization might need to design a teleprocessing monitor that monitors the transfer of data between multiple local and remote terminals. Sometimes, the system may be file-based with incompatible files which might eventually be required to move into an upgraded database-management system.
Rather than being organised as a set of interacting objects, most of the legacy systems had been designed long back using a function-oriented design strategy. To support function-oriented design, several methods and CASE (Computer Aided Software Engineering) tools are available and this approach is still used for many business applications.
It is expensive and risky, at the same time, to either replace or maintain legacy systems. With the aid of re-engineering, businesses may choose to extend the system lifetime, but that involves weighing up of both cost and risks.
In order to remain useful, systems have to be upgraded with time. It should be possible, principally, to replace a layer in the system leaving the other layers unchanged but in practice, this is near to impossible. The reasons behind are:
Being much more than mere application software, legacy systems also include business processes and supporting software and hardware. And hence, the business value of a system and its quality should be used to choose an effective evolution strategy.
White Paper By: Kenandy
In a technologically advanced world, why are there still so many companies using outdated legacy ERP software systems to manage their business operations? Why don't they simply switch to an updated and efficient management solution? Today’s tech-driven economy requires companies to adapt forward-looking, innovative solutions to compete. Cloud ERP solutions are now enabling...
White Paper By: Zeenyx Software
When a legacy application is modernized, transaction flow may be changed to adjust to the standards and capabilities of the new platform. If tests are automated using a traditional testing tool, those user interface changes would require a significant amount of test maintenance to get tests running on the new platform. AscentialTest provides a short-cut by allowing users to develop...
White Paper By: Kenandy
The vast majority of companies start out by using QuickBooks as their first accounting product. Most of the organizations gradually implement various workarounds, as the pain points of relying on a tool designed for small businesses increases. A growing manufacturing company requires capabilities that go beyond entry-level accounting products augmented with add-ons. Here, the next logical...
White Paper By: Mint Jutras
Cloud ERP for manufacturing is now becoming an integral part of the business operations of the major manufacturing concerns. A survey was conducted to investigate cloud ERP goals and benchmark performance of cloud based ERP implementations in light of the changing operational landscape for manufacturers. Moving to a subscription licensing and cost model, the ability to access anywhere,...
White Paper By: HSO
The commitment of an integrated ERP (Enterprise Resource Planning) solution can inspire any business owner to approve a costly, time-consuming planning and execution process. However, not all ERP implementations are successful; many end in frustration, failure and wasted resources. To prevent a disaster with your ERP implementation, arm yourself with the right resources to avoid such...
White Paper By: 9Dots Management Corp, LLC
The proactive planning and analysis components of a comprehensive, enterprise planning system enables any organization to quickly deliver a sophisticated, linked planning model that accurately reflects business in all its inevitable complexity and detail.Is your organization able to employ the best practices for proactive planning, budgeting, forecasting and analytics? This whitepaper...