Enterprise Application Integration - Communication Architectures

Communication Architectures

Currently, there are many variations of thought on what constitutes the best infrastructure, component model, and standards structure for Enterprise Application Integration. There seems to be consensus that four components are essential for a modern enterprise application integration architecture:

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.

Although other approaches like connecting at the database or user-interface level have been explored, they have not been found to scale or be able to adjust. Individual applications can publish messages to the centralized broker and subscribe to receive certain messages from that broker. Each application only requires one connection to the broker. This central control approach can be extremely scalable and highly evolvable.

Enterprise Application Integration is related to middleware technologies such as message-oriented middleware (MOM), and data representation technologies such as XML. Other EAI technologies involve using web services as part of service-oriented architecture as a means of integration. Enterprise Application Integration tends to be data centric. In the near future, it will come to include content integration and business processes.