Every organization has its own infrastructure that consists of systems, applications, people and processes. Though the infrastructure is unique to an organization as its culture and business model, in most of the organizations many processes were initially linked and owned by a department. Traditional IT systems were built to support these processes and connect people to them. That was resulting to more no of standalone application inside an enterprise which are addressing & solving very narrow problem within departament.
Since the data and the users of these applications existed within a single department, there was not so much thought given in sharing information with other systems. This led to building systems with no application programming interfaces, no open architecture, or other mechanisms that could allow the access to data and processes hosted by these systems. During the coming years, the business environment evolved tremendously with new business drivers having a great impact to organizations. Traditional boundaries between functional units have to be crossed forcing processes and data to be exchanged between departments. A typical new business driver is the demand to support new distribution channels like desktop browsers and intelligent devices apart from email and telephone. Merger and acquisitions usually add new monolithic systems into an enterprise. The real value of such a business driver can be realized only when any data and processes residing on these systems is integrated and merged with existing systems. Integrating the supply chain is just another business driver with similar impact. These are just some examples of business drivers that lead to enterprise application integration (EAI). So EAI is the ability to share data and business processes that span across many systems and departments as if they were on a monolithic and unified system.