Fiber Distributed Data Interface (FDDI)
Fiber Distributed Data Interface (FDDI) is a standard for data transmission in a local area network. It uses optical fiber as its standard underlying physical medium and provides 100 Mbit/s on a ring topolgy.
FDDI was used in the early to mid 1990s at a time where other LAN standards like Ethernet (10 Mbit/s), Token Ring (4 Mbit/s) or Arcnet (2 MBit/s) offered much lower speed. By the second half of the 1990s, FDDI was largely replaced with the lower-cost Fast Ethernet technology.
Please see The FDDI page in our wiki for the [limited] information we've gathered so far. Contributions are more than welcome!