State-based Publish/Subscribe

Definition

State-based publish/subscribe is an instance of the publish/subscribe concept. However, it is distinguished from other publish/subscribe approaches by maintaining partial matching state when processing publications, whereas, traditionally, publish/subscribe treat publications as transient and does not manage matching state. State-based publish/subscribe support the detection of composite events, event correlation and complex event processing.

Key Points

In terms of publishing, subscribing, and decoupling, state-based publish/subscribe is no different from topic-based or content-based publish/subscribe. The main difference to the other publish/subscribe approaches is that state-based publish/subscribe treats publications as non-transient. A publication is processed by the publish/subscribe system and builds up partial matching state, contributes to existing partial matching state, triggers notifications if a match is complete, or is discarded, if no matching subscription...