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 a switching role in the network are bridges, routers, switches, and gateways
. Components at the endpoints of a network include servers
that areconnected to the network through network interface cards
(NICs). 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 implementingAPPN PU 2.1, Advanced Peer to Peer Networking Physical Unit.