The Xalian buildsmiths have evolved a new form of transport system. Recognising that their smaller fighter craft are incapable of interstellar travel the buildsmiths developed star portal technorganic drivers.
The portals consist of two components, the portal aperture and the drive wave generator. The combination of which generates a tunnel into hyperspace through which fighters can enter and emerge in another quadrant of the galaxy.
Difficult to defend, Star Portals are normally located deep within Xalian held space, delivering their payloads at vast distances from their intended targets.
This is really quite a beautiful structure. I think that it would perhaps have more visual impact as just the one ring. I love how LDD allows one to clone segements like this for big structures and not to have to scour Bricklink in order to do it.