Now we have JMS for Java-based enterprise applications and AMQP for all other application needs. Why do we need a third technology? It is specially designed for small devices. Devices with low computational performance cannot accommodate complex operations on AMQP, they need a simple and interoperable way to communicate. This is a fundamental requirement of MQTT, which today is one of the main ingredients in the Internet of Things (IOT) ecosystem.
The following are the main features of MQTT:
1. Stream-oriented, low memory footprint
2. Designed for sending short messages between small silent devices with low bandwidth
3. Does not support long-term storage and forwarding
4. Does not allow segmented messages (hard Sending long messages)
5. Supports topic pub-sub
6. Does not support transactions (only basic acknowledgements)
7. Messages are actually ephemeral (short period)
8. Simple username and password, based on security without sufficient information entropy
9. No Supports secure connections
10. Messages are opaque
11. Topic is global (a global namespace)
12. Supports the latest value queue (Last Value Queue (LVQ))
13. Client and server are asymmetrical
14. Cannot be extended