Event Queues

Overview

An event queue is an event-based publish-subscribe solution for application information delivery and messaging. It provides asynchronous communications for different modules/roles in a loosely-coupled and autonomous fashion.

By publishing, a module (publisher) sends out messages without explicitly specifying or having knowledge of intended recipients. By subscribing, a receiving module (subscriber) receives messages that the subscriber has registered an interest in, without explicitly specifying or knowing the publisher.

The purpose of event queues are two folds:

1. Simplify the many-to-many communication.
2. Make the application independent of the underlining communication mechanism. The application remains the same, while the event queue can be implemented by use of Ajax, server push and even message queue.