Messaging Systems and the Java Message Service

What is a Messaging System?

In its essence, a messaging system allows separate, uncoupled applications to reliably communicate asynchronously. The messaging system architecture generally replaces the client/server model with a peer-to-peer relationship between individual components, where each peer can send and receive messages to and from other peers.

Messaging systems provide a host of powerful advantages over other, more conventional distributed computing models. Primarily, they encourage "loose coupling" between message consumers and message producers. There is a high degree of anonymity between producer and consumer: to the message consumer, it doesn't matter who produced the message, where the producer lives on the network, or when the message was produced.

This permits dynamic, reliable, and flexible systems to be built, whereby entire ensembles of sub-applications can be modified without affecting the rest of the system.

Other advantages of messaging systems include high scalability (commercial implementations boast the ability to support tens of thousands of clients and tens of thousands of operations per second), easy integration into heterogeneous networks, and reliability due to lack of a single point of failure.

Because of the reliable and scalable nature of messaging systems, they are used to solve many business and computing science problems. For example, they are the basis of such diverse applications as workflow, network management, communication services (voice over IP, voicemail, pager, email), customer care, weather forecasting, supply chain management, and many other systems. In addition, messaging systems are also invaluable as "glue" to bring together the disparate systems that inevitably result from mergers and acquisitions.