JMS – Publish/Subscribe Messaging Domain (Magic xpi 4.9)
In a publish/subscribe (PSS) product or application, clients address messages to a topic. Publishing and subscribing objects are generally anonymous and may dynamically publish or subscribe to the content hierarchy. The figure below shows how a PSS domain manages the distribution of messages arriving from a topic's publishing object to multiple subscribing objects. Topics retain messages for only as long as it takes to distribute the messages to current subscribers.
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JMS – PSS Characteristics