First, a little about me. I began working on SAP ABAP, but groping with XI and learning the tricks of this trade now. This is my first blog posted in SDN. This blog will give an over all idea about Enterprise Application Integration (EAI), which can be useful for anyone starting on XI (or any other middleware Technologies)
Enterprise Application Integration:
In earlier days companies bought software solutions like SAP, PeopleSoft, Oracle ERP, IDEdwards, Siebel etc. and those software solutions would work very well individually, but create silos of information. In many cases each individual system produced excessive information. When common information changed, we updated the information in each system manually and the process became difficult to handle. Ultimately some of the data across the system became inconsistent. When people noticed those resulting inconsistence in data and double entry data, they decided to get ways to integrate the systems. From that EAI (Enterprise Application Integration) was developed.
EAI allows the flow of information across the different systems. By connecting the different processes ,softwares and hardwares of more enterprises to become one enterprise system. The main motto of the Enterprise Application Integration is to condense the efforts needed for designing and coding. And it allows reuse of configurations or codes for the new system. It reduces the maintenance costs and difficulties of the custemers.
The main objective of the EAI :
In EAI there are two logical integration architectures. Direct point-to-point connects and middleware based integration.
EAI developer follow point-to-point integration because they found it easy to understand and it can implement quickly for few systems to integrate. One example of point-to-point integration is one application makes direct database connection calls to another application’s database tables. Initially when we integrate two application systems the point-to-point integration is right choice. When we integrate additional applications we get a situation shown in below figure.
Later stages of a point-to-point integration
In this each application is tightly coupled with the other applications through point-to-point connection. If we change one application it may break the other integrated applications. If we have five applications to be integrated with each other we will need ten different integration points showed in below figure.And each additional application becomes difficult to integrate and maintain.
More point-to-point connections
To avoid those problems we required an intermediate layer to isolate the changes in one application from the other applications.
Middleware provides interfaces with all integrated applications passing messages to each other and each interface defines a business process provided by the application. The below figure shows the service-oriented architecture using middleware.
Service-oriented architecture adds and replace applications without affecting the other applications. If we have ten applications to integrate we will have just ten integration points. It supports a larger number of integrated applications and less maintenance. Middleware can perform complex operations from application to applications.
The additional complexity is setting up the middleware and converting the existing application to use the middleware API.
Major EAI Solution Providers:
EAI can integrate Legacy / Mainframe, Client-Server, Web, e-Commerce, ERP / CRM / HRMS, Custom applications, etc. Various functionalities of EAI are Messaging ,Interfacing, Transformation, Routing and Process Modeling.
I hope this sneak peak into EAI was interesting to some of you. If you find any errors or have other input don’t hesitate to comment here.