Source : Free On-Line Dictionary of Computing

Copper Distributed Data Interface
     
        (CDDI) {FDDI} running over conventional copper cables.  A
        {Cisco}/{Crescendo} copyright term(?).  All {FDDI}
        connections, {single-attached} or {dual-attached}, can be
        either {optical fibre} or copper.
     
        (1994-12-14)