Computer Networks

A network is a collection of personal computers and peripherals that are interconnected by means of cables or wires to share programs and data. 

The network has a server-PC that acts as the storehouse and distributor for the programs, data and the peripherals to be shared.  The network operating system provides the communication-link between all the PCs on the network. 

The most popular network operating system at this time is NetWare. 

The Network Operating System (NOS) is installed in a PC on top of its regular operating system (DOS etc.).  It is there as an extra layer having approach to the network-wide management.  The PC’s regular operating system plays a second fiddle to the network operating system. 

How it works

The Network Operating System acts as an invisible layer between the PC’s operating system (DOS etc.) and the user’s application.  It acts as under: 

1)     The user requests for a particular file to the Network Operating System. 

2)     The Network Operating System examines the request and  

    (a)   if the requested file is there on the user’s own PC, the Network Operating System passes on the request to the PC’s operating system.  The operating system retrieves the file and passes it down to the user’s application. 

    (b)   if the requested file is there on the server-PC of the network, the Network Operating System passes the request to the server-PC.  The server-PC at once retrieves the file and transmits it to the user’s PC. 

3)     The Network Operating System of the PC receives the file and passes it down to the user’s application. 

PCs connected to a network system are called its workstations.