legacy system


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Related to legacy system: Legacy software

legacy system

[′leg·ə·sē ‚sis·təm]
(computer science)
A computer system that has been in operation for a long time, and whose functions are too essential to be disrupted by upgrading or integration with another system.

legacy system

(jargon)
A computer system or application program which continues to be used because of the cost of replacing or redesigning it and often despite its poor competitiveness and compatibility with modern equivalents. The implication is that the system is large, monolithic and difficult to modify.

If legacy software only runs on antiquated hardware the cost of maintaining this may eventually outweigh the cost of replacing both the software and hardware unless some form of emulation or backward compatibility allows the software to run on new hardware.

legacy system

An older computer system such as a mainframe or minicomputer. It may also refer to only the software (see legacy application).
References in periodicals archive ?
Though the IT department and users will need to learn new ways to interact with the reborn legacy system, they will still be dealing with the same logic.
NAYLOR: A customer's decision to replace a legacy control system typically revolves around increased cost of ownership to continue to service and maintain the older legacy system, the need to be able to do more with their system in terms of plant performance and third party application integration, and a recent trend by vendors to declare their legacy systems "end-of-life" forcing customers no alternative but to replace their older system with a newer one.
Therefore, a legacy system is an operational system that was written using hardware and/or software which is no longer seen as part of the organization's current strategy.
You can marry your legacy system to the client-server platform by incorporating a graphical user interface.
It also allows insurers--both life and property/casualty companies--to connect their information-rich but outdated legacy systems to new, Web-based technology.
The ability to distribute drawings and models through the Internet has increased the utilization of our legacy systems, so we could immediately begin reducing expenses and increasing productivity, allowing us to stay more competitive in our market.
In effect, it's like old wine in new bottle - bringing the best solution to users who simply cannot replace legacy systems without major disruptions, downtime, lost business and impending calamities" explained Mr.
Software AG's ApplinX product will enable organizations to more easily and comprehensively integrate their legacy systems with Service Oriented Architectures (SOAs).
P&H's Legacy Systems Migration program is the industry's first comprehensive set of products and services developed specifically to help financial institutions migrate their legacy cash management systems to a technologically advanced environment in a timely fashion and with a minimum of disruption.
Business logic within an application represents the business policies and procedures that state what needs to be done by an application and is the most important element of legacy systems that needs to be extracted and implemented in more modern architectures.
Users can import an entire XML schema as a target (or any manageable subsection of a schema) and can map from their existing legacy system records.