What is the difference between Durable and non-Durable subscribers?
The main difference between durable and non-durable subscriber is that durable subscriber gets every message sent to the topic once it subscribes to the topic, but non-durable subscriber only gets message sent to the topic during its life time. Once a durable subscriber subscribes to a topic, even the client application exits and then starts up again later, the subscriber is still able to get all those messages sent to the topic when it is offline. But if a non-durable subscriber client application exits and then starts up again, the non-durable subscriber does not get messages sent when it is offline. It only carries on receiving from the point where it starts up again.
