Understanding the (self-hosted) openHAB cloud

Hi,

I’m trying to understand how to make this openHAB cloud solution work.
Now, I’ve installed the node packages so the “app” is running on a separate host. However I don’t understand how the communication between openhab and the OH cloud app actually works and if I’m suppose to expose port 3000 to the internet ? Couldn’t find specific docs on this…

Also, my config.json on the “app” has the system section defined with my openhab IP as the host and port 443, this shouldn’t work as there is nothing listening on port 443 on my openhab host as far as I can see, yet the cloudbinding and node app says everything is working fine…how could this be?

   "system": {
      "host": "192.168.1.100",
      "port": "443",
      "protocol": "https",
      "logging": "debugging",
      "subDomainCookies": false,
      "muteNotifications": false

I can see the Nginx server is optional but optional how? does it make the solution more secure ?
Am I getting this all wrong … :worried:

Anyone?

is port 3000 supposed to be a forwarded port (NAT)?
What “system” is supposed be set in the config.json?