Source : Free On-Line Dictionary of Computing

Fiber Optic InterRepeater Link
     
         (FOIRL) An older standard of {fiber optic} guides
        used for carrying 10 MBps {Ethernet}.  The maximum length of a
        {segment} is 1 km.  A FOIRL {multiport repeater} and
        transceivers are necessary to carry the signal to multiple
        devices.
     
        The more recent version of Ethernet over fiber optic cables is
        {10baseFL} with a maximum segment length of 2 km.
     
        (1998-06-28)