A network node( NN) is an active network component that can be located within the network structure or at the end points of the network. Nodes that play an intermediary role in the network are bridges, routers, switches, and gateways.
In the SNA architecture, a network node is an intermediate node that provides connectivity, directory services, route selection, data transport, and network management. The SNA Network Node contains the Control Point( CP) that manages the Network Node (NN) and Low Entry Networking( LEN) resources in that domain. The Network Node can support intermediate routing services by implementingAPPNPU 2.1, Advanced Peer to Peer Networking Physical Unit.