(1) An access point through which a user or application program accesses the SNA network to communicate with another user or application program.
(2) A unit of linear measurement. For example, in Mixed Object Document Content Architecture (MO:DCA) and AFP data streams, the following measurements are used: 1 L-unit = 1/1440 inch, 1 L-unit = 1/240 inch.
(3) In open systems, a logical disk drive.
(4) A device or controller to which Small Computer System Interface (SCSI) commands are addressed, such as a virtual disk (VDisk) or managed disk (MDisk).