Starbase-51 was one of the original portal stations built after the creation of the Core. As with all Portal stations it was designed primarily to act as a frontier entry port to and from the Core and as such is heavily guarded and armed. Although run by Gal-Fed administrators there is no doubt that the Core truly runs this station, as it does all other Portal stations.
As trade between the Core and the Sphere has dropped off over the centuries all of the Portal stations have had to adapt to stay in business. Starbase-51 has been extensively rebuilt since it's axis was first laid down and now boasts state of the art ship repair facilities and a fully equipped medical facility, although this is not up to the standard of the Gentry Medical Station also within this system, and has had several decks converted to accept factory modules.