TIBCO EMS STEP -3

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Ø  Publish and subscribe message system, producers address messages to a topic. In this model, the producer is known as a publisher and the consumer is known as a subscriber.
Ø  Many publishers can publish to the same topic.
Ø  A message from a single publisher can be received by many subscribers.
Ø  Subscribers subscribe to topics, and all messages published to the topic are received by all subscribers to the topic.
Ø  This type of message protocol is also known as broadcast messaging, because messages are sent over the network and received by all interested subscribers.
Ø  Example: similar to how radio or television signals are broadcast and received.


Ø  Durable Subscribers for Topics: to ensure that messages are received, even if the message consumer is not currently running.
Ø  Durable subscribers can receive messages from a durable subscription even if the Subscriber was not available when the message was originally delivered. When an application restarts and recreates a durable subscriber with the same ID, all messages stored on the server for that topic are delivered to the durable subscriber.
Ø  Shared Subscriptions for Topics:  Shared subscriptions allow an application to share the work of receiving messages on a topic among multiple message consumers. When multiple consumers share a subscription, only one consumer in the group receives each new message.
Ø  A topic can have a mix of shared and not shared, durable and non-durable consumers. When a message is published to the topic, the same message goes to all the matching subscriptions.

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