MQTT Protocol

• MQTT Protocol Overview
• Publish-Subscribe Architecture
• Broker and Client Roles
• Broker Comparison: Mosquitto vs EMQX
• Topic Structure and Hierarchy
• Single-Level Wildcards (+)
• Multi-Level Wildcards (#)
• Quality of Service Level 0
• Quality of Service Level 1
• Quality of Service Level 2
• QoS Comparison and Selection
• Retained Messages
• Birth and Death Messages
• Last Will and Testament
• MQTT Topic Best Practices
• MQTT CLI Operations
• MQTT Explorer Tool
• MQTT Client Setup
• JSON Message Construction
• MQTT Publish and Subscribe
• Callback Function Handling