(1) In a network environment, the route between any two nodes.
(2) The route through a file system to a specific file.
(3) In OSI, a description of how a local line or line set can be used for outbound communications.
(4) In SNA, the set of data links, data link control layers, and path control layers that a path information unit travels through when sent from the transmission control layer of one half-session to the transmission control layer of another half-session.