Enterprise Integration : Web Services, SOA, ESB and JBI

Web Service Specifications

These define standards-based implementation technologies for many of the Integration patterns, but use the same architectural principles and guidelines.

Service Oriented Architectures 

Describe ways to build loosely-coupled systems composed from individual services. Because much of this loose coupling is a result of message-based communication between services, our patterns are extremely relevant in the SOA space.

ESB (Enterprise Service Bus)

The core of a typical service bus incorporates messaging, routing, transformation, endpoints.

Finally, the JBI (Java Business Integration)

JBI is the new integration API introduced in the J2EE world. It is a great enabler for SOA because it defines ESB architecture, which can facilitate the collaboration between services. It provides for loosely coupled integration by separating out the providers and consumers to mediate through the bus.

JSR 208 is an extension of J2EE, but it is specific for JBI Service Provider Interfaces (SPI). SOA and SOI are the targets of JBI and hence it is built around WSDL.

Case: Web Services without being SOA: Very much Possible. SOA is an Architecture and an application as such can have Web Services without really being SOA.

Case: Web Services & SOA without being an ESB: This can be a case where in you may commit to the concept of SOA but not necessarily implement ESB.

Case: Web Services, SOA & ESB

The JBI (Java Business Integration) case, following meta-model describes the constitution of the Architecture in context

Case: ESB and SOA without Web Services: Other Protocols such as JMS or Other Native Queuing forming the core messaging implementation you use.

Case: ESB without SOA: ESB implemented as Application Integration Technique without the consideration of SOA