IIoT of HMI 
This section talks about IIoT-related topics including:
MQTT & Basics
Learn about MQTT basics.- Pub/Sub MQTT Messages
Publish your device data to a MQTT server. - Use Sparkplug B to publish device data
Sparkplug B is a specification built upon MQTT as an efficient way to collect your machine data. - Connect your device to AWS IoT
Collect and control your machine using AWS IoT. 
- Pub/Sub MQTT Messages
 OPC UA & Basics
Learn about OPC UA basics.- OPC UA Server
Setup an OPC UA server on HMI/Gateway. - OPC UA Client
HMI can be an OPC UA client to collect and display data from another OPC UA server. 
- OPC UA Server