Talk:error/local hub/cannotregisternotavailablesite

This topic says: "To register to a hub your Moodle site needs to be accessible by the hub so the two can communicate bi-directionally." What does this really mean? How does the hub connect to a Moodle site? What protocold does it use to do the connection (http? https? Something else?)

What proxy and/or firewall rules need to be created to give "the hub" access to the Moodle site?