Corporate information drives the enterprise business. In many enterprise organizations, business critical information and data processing functions are on mainframe computing systems. In addition to the legacy host systems, today's enterprise also has a mix of highly specialized systems, many departmentally maintained. Each of these systems represents a significant investment and each is critical to successful business operations.
These organizations are finding an increased requirement to access and integrate these many computer systems. The problem is that these systems were never designed to work together, and they were not designed for Web operations (either internal to the organization or externally to the World Wide Web).
For years, IT departments have been trying to make information stored on one system available to other systems. Abandoning existing systems and starting from scratch to build a new enterprise-wide, one-system-fits-all data processing system is out of the question. The investment in mainframe legacy systems is too high. In addition, it does not make good business sense to abandon processing systems that are reliable and stable.
Enterprise Application Integration (EAI) by integrating legacy host systems with other data systems, in particular Microsoft Windows-based and Web systems is one solution to the problem. The ability to combine terminal-based host applications and databases with Windows-based applications is increasingly important to the overall data processing functions of the enterprise. When done successfully, legacy host integration eliminates the need to build laborious custom interfaces to link disparate applications and data. It addition, it also makes the host application completely invisible to the user.