IoT Protocols: MQTT, CoAP, and Beyond
IoT Protocols: MQTT, CoAP, and Beyond Small IoT devices face limits on power, bandwidth, and processing. Two popular protocols address these challenges in different ways: MQTT and CoAP. MQTT uses a central broker and a publish-subscribe pattern, while CoAP uses a lightweight REST-like model over UDP. Both aim to minimize overhead and support intermittent connectivity, so devices stay responsive without draining batteries. MQTT basics are simple. A client connects to a broker, publishes messages to topics, and subscribes to topics of interest. Messages carry a quality of service (QoS) level: 0, 1, or 2. The protocol keeps headers small, supports last-will messages, and can retain data for late subscribers. A common setup has a temperature sensor publishing to home/livingroom/temperature, while a dashboard subscribes to that topic to display readings in real time. ...