Notes:
From http://www.faqs.org/faqs/LANs/ethernet-faq and http://www.ethermanage.com/ethernet/enet-faqs/ethernet-faq.html
10BaseF, and its predecessor, FOIRL, are the only recommended topologies for inter-building links. However, they need not be limited to this role. 10BaseF can also be run to the desktop, though the cost is prohibitively high in all but the most specialized environments (generally, extremely noisy manufacturing facilities, or very security-conscious installations). More commonly, FOIRL (and now, 10BaseF) is used inside buildings to form backbone networks and to connect wiring closets together.