Computer Network

Computer Network

A computer network is interconnection of various computer systems located at different places. In computer network two or more computers are linked together with a medium and data communication devices for the purpose of communication data and sharing resources. The computer that provides resources to other computers on a network is known as server. In the network the individual computers, which access shared network resources, are known as nodes.

Parts of a network

There are five basic components of a network: clients, servers, channels, interface devices and operating systems :
» Servers
Sometimes called host computers, servers are powerful computers that store data or applications and connect to resources that are shared by the users of a network.
» Clients
These computers are used by the users of the network to access the servers and shared resources (such as hard disks and printers). These days, it is typical for a client to be a personal computer that the users also use for their own non-network applications.
» Channels
Called the network circuit, the channel is the pathway over which information travels between the different computers (clients and servers) that comprises the network.
» Interface devices
These are hardware devices that connect clients and servers (and sometimes other networks) to the channel. Examples include modems and network interface cards.
» Operating systems
The network operating system is the software of the network. It serves a similar purpose that the operating system serves in a stand-alone computer.

Importance of Networking

Networking of computers provides a communication link between the users, and provides access to information.
» Resource Sharing
In an organization, resources such as printers, fax machines and scanners are generally not required by each person at all times. Moreover, for small organizations it may not be feasible to provide such resources to each individual. Such resources can be made available to different users of the organization on the network. It results in availability of the resource to different users regardless of the physical location of the resource or the user, enhances optimal use of the resource, leads to easy maintenance, and saves cost too.
» Sharing of Information
In addition to the sharing of physical resources, networking facilitates sharing of information. Information stored on networked computers located at same or different physical locations, becomes accessible to the computers connected to the network.
» As a Communication Medium
Networking helps in sending and receiving of electronic-mail (email) messages from anywhere in the world. Data in the form of text, audio, video and pictures can be sent via e-mail. This allows the users to communicate online in a faster and cost effective manner. Video conferencing is another form of communication made possible via networking. People in distant locations can hold a meeting, and they can hear and see each other simultaneously.
» For Back-up and Support
Networked computers can be used to take back-up of critical data. In situations where there is a requirement of always-on computer, another computer on the network can take over in case of failure of one computer.