From the Sun website:
The J2EE Connector architecture is based on the technologies defined and standardized in the Java 2 Platform, Enterprise Edition (J2EE) and is part of the J2EE platform.
As more businesses move towards an e-business strategy, integration with existing enterprise information systems (EIS1) becomes the key to success. Enterprises with successful e-businesses need to integrate their existing EIS systems with new web-based applications. They also need to extend the reach of their EIS systems to support business-to-business (B2B) transactions.
Before the the J2EE Connector architecture was defined, no specification for the Java platform addressed the problem of providing a standard architecture for integrating heterogeneous EIS systems. Most EIS vendors and application server vendors use non-standard vendor-specific architectures to provide connectivity between application servers and enterprise information systems. The following diagram illustrates the complexity of a heterogenous environment.
