what is EAI?

EAI

   1. A centralized broker that handles security, access, and communication. This can be accomplished through integration servers (like the School Interoperability Framework (SIF) Zone Integration Servers) or through similar software like the Enterprise service bus (ESB) model that acts as a SOAP-oriented services manager.
   2. An independent data model based on a standard data structure, also known as a Canonical data model. It appears that XML and the use of XML style sheets has become the de facto and in some cases de jure standard for this uniform business language.
   3. A connector, or agent model where each vendor, application, or interface can build a single component that can speak natively to that application and communicate with the centralized broker.
   4. A system model that defines the APIs, data flow and rules of engagement to the system such that components can be built to interface with it in a standardized way. This aids Orchestration

Advantages

• Real time information access among systems
• Streamlines business processes and helps raise organizational efficiency
• Maintains information integrity across multiple systems
• Ease of development and maintenance

Disadvantages

• High initial development costs, especially for small and mid-sized businesses (SMBs)
• Require a fair amount of up front business design, which many managers are not able to envision or not willing to invest in.

Most EAI projects usually start off as point-to-point efforts, quickly becoming unmanageable as the number of applications increase.

SOA is a loosely coupled solution to replace EAI (didn't kill EAI though).