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Queues are typically used for storing messages until a subscriber connects to the MB and consumes them. Therefore, queue subscriptions are inherently durable.. A JMS client can then subscribe to the queue at any time and consume the messages stored for the queue. Unlike with Queues, Topics in WSO2 MB are typically used for realtime message brokering. That is, messages published to a topic are required to be delivered to all the active subscribers instantly (in realtime). Messages that are published to a topic while a subscriber is inactive will be handled according to the durability of the subscription as explained below.
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