ESB and JBI

ESB and JBI

from http://blogs.sun.com/rtenhove/entry/esb_and_jbi

I am often asked what the relationship is between Enterprise Service Bus (ESB) and Java™ Business Integration (JBI). There is often an assumption that JBI defines an ESB, but this isn't true. JBI defines a part of an ESB: the service container.

The service container is the point where integration really happens: where IT assets (applications, protocols, databases, even data files) are turned into providers of services, consumers of services, or even both. Service containers have to deal with a wide variety of technologies, and "map" them to (and from) a standard services model.

JBI is the perfect means for constructing such service containers. It provides a standardized, plug-in architecture for bringing the right technologies to bear on particular integration tasks. The WSDL services model built into JBI is perfectly aligned with the standard services model needed for the ESB. Pragmatically speaking, building service containers from standard components is far more economical than custom-building them, or using proprietary adapters.

Service containers are not the whole ESB story. The ability to create a distributed set of service containers, linked by reliable messaging infrastructure, intelligent message routing, and administered centrally are all features outside the service container itself (and thus, outside of the scope of JBI 1.0).

Several open-source projects have taken this basic idea, and are in the process of creating cool new ESBs. These include:

• Project Open ESB. This is Sun's open-source ESB, based directly on the JBI technology.
• Apache ServiceMix.
• Celtix.
• Mule.
• ESB initiative (ESBi).
• PETALS.
• Synapse.

My apologies to any projects that I missed. (Note that there are at times complex inter-relationships between some of these projects.) There are also commercial products in the pipeline, but vendors are typically less open about their development efforts, so they will have to speak for themselves.

As you can see, JBI has found a place in the world of ESB! This is a great benefit to users of both the open-source ESBs and the commercial ones: JBI standardizes what is easily the most complex (and costly) pieces of an integration fabric. By avoiding having to reinvent application adapters for each new ESB implementation, the ESB architects can concentrate on innovating in what their ESB's do. This delivers more value to customers. Standardized integration components lower costs, and help avoid the hazards of vendor lock-in. So if you are looking for an ESB, look for JBI support. If you are exploring the ideas around ESB and SOA, check out the open-source projects listed above.