EAI or Enterprise application integration is a term used to describe an integration (sharing) of data between different application or software.Why do we need to have EAI ?
From my understanding, EAI is needed to avoid the isolation of data and to keep each data across the whole company in sync. For example, let say in a bank where only two different system is used: .NET custom software and Siebel package software. Understand that Siebel software has its own database whereas .NET may use SQL Server as their database. However, in the bank, there is a need to share data between .NET and Siebel system. So in this case, how could one keep both data in .NET database and Siebel database in sync? That is why EAI comes to play.

What is need to have an EAI call?
EAI call occurs when there is a need to integrate data accross platform to keep both platforms in sync. In this case you would need:

• Caller Application (The one who make the call)
• Receiver Application(The one who recieve the call)
• Middle ware (The system to help integration of data possible)

Note: The information is based on my 6 months+ experience working in a Siebel environment. Hence, bear in mind that information sharing may not be fully explained.

In Inland Revenue Authority of Singapore, I work as an IT Analyst Programmer. My responsibilty is to build and fix problems relating to Siebel Package Sofware. So, here i would like to try to explain in a layman term, what Siebel actually is.Siebel is a leading package software for CRM (Customer Relational Management). Many international corporations use this package software (Siebel) to help them retains their employees, making customers happy and to eliminate the paper works.

An example would be a Call Center. For example, the first time you book a taxi, the operator would ask about your particulars such as your name, your phone number and your location. This data will be captured to the Siebel database. The next time you call in, You would not need to supply your particular again; it is as if the taxi operator knows you. Indeed, the operator knows you because once you made a call, your phone number will be transfered to the Siebel Package software and do a lookup to the siebel database to retrieve your particulars. Can you imagine that everytime you call a taxi in singapore, and you will have to tell the operators again and again about your phone number, your name and your location? This is how Siebel helps corporation to achieve the satisfaction of their customers.

I hope this could explain what Siebel or CRM is and why corporations use it.