Computer network

What is Computer Network-

A computer network is a group of computers, and peripheral devices connected through a data communication system. It facilitates the sharing of hardware and software resources among different users working on different computers. These shared resources can be data files, any application software or hardware devices likes printer modem. etc.

Advantage of network-

Hardware & Software sharing:- 

In a computer network, data, s/w, h/w resources can be shared irrespective of the physical location of the resources and the users. All these devices are attached to the server, which is shared among number of users.

Reliability:-  

A file can have its copies on two or more computer of the network, so if one of them is unavailable, the other copies could be used. That makes network more reliable.

Reduced cost:-

In a network, we can share almost every peripheral device, such as printer scanner, modem etc. among several computers. This reduce the cost of hardware. 

Fast communication:-

With network, it is possible to exchange information at very fast speeds.

Evolution of Networking:-

ARPANET :- 

The first network was developed in 1969, when the US Defense Dept. sponsored a project named ARPANET (ADVANCE RESEARCH PROJECT AGENCY NETWORK). It was developed by Robert Kahn And Vint Cerf 

NSFnet:-

In 1980, NSFnet (National Science Foundation) was started to make a high-capacity network to be used strictly for academic and engineering research.  It is more capable than ARPANET.

Internet:- 

In 1990,  the internetworking of ARPANET , NSFnet and other private networks resulted into internet.

KINDS OF NETWORKS?

Depending on one’s perspective, we can classify networks in different ways:-

• Based on transmission media: Wired (UTP, coaxial cables, fiber-optic cables) and Wireless
• Based on network size: LAN ,WAN (and MAN)
• Based on management method: Peer-to-peer and Client/Server
• Based on topology (connectivity): Bus, Star, Ring, Mesh …

COMPONENTS OF COMPUTER NETWORK:-

There are many components of the network, which share common devices, functions & features including

Server-

A server provide services to other computers, which holds stored files, programs and network operating system.

Client-

The client computer access network & shared resources provided by the server. It is less powerful than server computer.

Transmission Media-

Transmission media interconnect the computers in a network.

Different types of transmission media are, Wired or Bounded and unguided or wireless.

Network Interface Card (NIC):-

It is also known as adopter. NIC regulates the exchange of data between the network and the computers.

Protocols:-

A set of rules is called protocol. network protocol is standardized set of rules used for transmission of data and/or establish communication between them.

Resources:-

The hardware that are available to a computer on a particular network are known as resources.