Enterprise Service Bus (ESB)
Enterprise Service Bus (ESB) evolved to be the next generation of enterprise integration solutions, with message-oriented middleware (MOM) and web services being considered the closest relatives. However, ESB has a broader scope than MOM. For instance, ESB includes such services as coordination of business processes, or protocol transformation, that normally lay out of scope of MOM. Protocol transformation is one of the key features of ESB, aimed at providing communication between various incompatible systems without writing (otherwise necessary) adapters. For example, ESB can provide a MQ Series-to-WAP transformation facility for publishing mortgage rates on mobile devices. In contrast, MOM usually supports a single transport mechanism, and its services, therefore, significantly rely on underlying message protocols, messaging data formats, error handling mechanisms, and so on.
ESB also has a broader scope than web services. For instance, web services frameworks usually lack such features as publish-subscribe messaging models (the WS-Notification family of protocols is a fairly new development in this field) or protocol transformation.
The comparison matrix below highlights some of the feature differences between JMS, web services, and ESB (of course, this table matrix is not a complete feature comparison).
ESB Vs MOM and Web Services
| ESB | MOM | Webservice | |
| Transport layer | JMS provider, SOAP provider, WSDL provider, Stream provider, File provider, and more. | JMS | SOAP over HTTP |
| Mediation and rules | Protocol translation, routing, and data transformation | Routing and data transformation | Data transformation |
| Deployment | Maximum level of flexibility for dynamic configuration | Requires recompiling client code | Requires recompiling stubs |
Enterprise Service Bus (ESB) evolved to be the next generation of enterprise integration solutions, with message-oriented middleware (MOM) and web services being considered the closest relatives. However, ESB has a broader scope than MOM. For instance, ESB includes such services as coordination of business processes, or protocol transformation, that normally lay out of scope of…