Being able to connect and share information between two or more, often heterogeneous and most commonly distributed, systems (or applications or components) is a very common challenge in IT management. Historically, solving this involved binding the systems together with proprietary hard-coded connections. Consequently, the systems became tightly coupled as they had to be highly aware of each other. In practice, it became impossible to change one system without making changes to any other.

With the advent and use of Message-oriented Middleware (MOM) and the inherent message broker component, the systems became more loosely coupled. The terms "MOM" and "message broker" are often used interchangeably, and they normally denote the software (or hardware) component responsible for actual message transportation. Loose coupling means that the systems no longer need to directly know about, and depend on, each other's API interfaces or inner workings. Changes to one system...