Definition(s)
Router
Gateway between two networks at OSI layer 3 and that relays and directs data packets through that internetwork. The most common form of router passes Internet Protocol (IP) packets [11].
Source: ANSI/ISA–99.00.01–2007, Security for Industrial Automation and Control Systems, Part 1: Terminology, Concepts, and Models, 29 October 2007. National Standard