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Integration Requirements and Scenarios

bining two divergent information technology (IT) systems. Not only are the IT

systems different, but, as a further challenge, they each may have standardized on

using different integration technologies within their respective environments.

Emerging Web services standards are another factor driving Web services based

EAI. These standards are making it possible to integrate heterogeneous systems

easily and cost effectively.

In today's environment, a typical enterprise has a multitude of existing appli 

cations running on diverse platforms and operating systems. Although these appli 

cations may very well rely on the same or similar data, they keep that data in

different formats. Thus, the integration problem encompasses both data and

system platforms.

These are but a few examples of the complexities that enterprise application

integration must address. Not only must EAI handle integrating applications, it

must also address integrating data and technologies so that enterprises can easily

share business processes and data.

Using several scenarios, this chapter illustrates key integration considerations.

It describes the J2EE 1.4 platform technologies that help with integration and pre 

sents some  and guidelines.

6.1

Integration Requirements and Scenarios

Before delving in the details of the technologies, it is helpful to illustrate the major

concerns for integrating enterprise information systems and to get a sense of the

extent of the EAI problem. We discuss three types of integration scenarios: data

integration, application integration, and business process integration. Often, an

enterprise's integration needs span these different types. 

6.1.1 Typical Integration Scenarios 

Data integration involves integrating existing data living in different enterprise sys 

tems, and it often occurs when an enterprise relies on multiple types of database sys 

tems. For example, some database systems may be relational, others may be

hierarchical or based on objects, and still others may be file based or even legacy

stores. As an illustration, a newly developed Web based order management system

might have to integrate with an existing customer order database. Data integration

involves not only integrating different data systems, but it also entails integrating

different informational or data models.