The Reference Model and its Layers

Abstract

A net is a set of nodes connected by arcs. The computer network is a net, too, but its nodes are data (information) processing systems and its arcs are data communication channels. In other words, the computer network is a system of communicating computers automatically exchanging information among the machines and interactively sharing the resources available. Interactive sharing means that any node can access any other remote node of the network as if it was a local resource. (The expression “network” is generally used for a computer network. If not, the readers’ attention will be drawn to it.) The resources can be either hardware or software resources. The sharing of resources is economically effective; a single, very special, rarely used resource can become common property for all network users. The advantage is not only economic, but the power of the computers is multiplied too. Dynamic file access, the sharing on remote data and remote programs is not only useful but it also allows the homogeneous loading of the network.