MQTT - A Protocol for Connecting IoT Devices
MQTT is a really simple protocol that connected devices can use to publish and receive messages. Messages have a topic and may contain an arbitrary payload. Devices never talk to each other directly. A server (MQTT broker) receives published messages and distributes them to subscribers by matching message topics with subscribed-to topics.
- MQTT Encoding and Decoding
- Handshaking - a FSM (Finite State Machine) of the protocol at QoS 0, 1, 2
- Limits of the Arduino environment (like, conversational state)