Once a node is activated with the Automation Gateway module, the node scans all directly connected network segments for management services (e.g. HTTPS web GUI or REST API running on a device such as a firewall appliance or an iDRAC running on your Dell Server). These discovered management services are published on Lighthouse via its API and web GUI.
When a Lighthouse user or automation code needs to access the remote device, Lighthouse proxies the connection via its local IP address, through to the remote device IP.
More simply put, when a user needs to access the web UI of a firewall on a remote, unreachable network, they browse to Lighthouse, search for the firewall, click a link, and the web UI is displayed.