Communication and networking

Introduction:

computer network is a group of computer systems and other computer devices that are linked together through communication channels to provides communication and sharing through of resources among wide range of user . Computer networking is the process of linking two or more computer devices together for the purpose of data and sharing .

The first computer network called ARPANET( Advance resource project Agency Network ) was developed by ARPA in 1960's for US defense army . After decide it was released for public.

 Purposes of computer network

• Facilitate communication through e-mail instant machining , video conferencing .
• Enable multiple user to share a single hardware devices like ; printer , scanner , etc.
• Enable file sharing approach the network .
• Allow for sharing of software or operating programs on remote system.
• centralizing administration and support .
• Make information easier to access and maintain along network users.

Advantages of computer network:

a) sharing of resources:

A computer system consists of various kinds of hardware and software resources using computer network , it is possible to share resources like: file, data, software or hardware. A single file can be shared and used by multiple users at the same time. similarly  a single hardware also can be shared among multiple users.

b) Increase storage capacity :

In a computer network multiple computer are interconnected in which computer has limited storage capacity of such computers can be used for storage.

c) Cheaper and faster communication:

Using a computer network data, information, messages, can be easily transferred from one computer to another computer at high cost and minimum transmission cost.

d) Centralized control:

In a computer network, multiple computers are interconnected to a single server. There are many essential networking policies, rules or networking issues which are implemented on the server and such polices are automatically transferred to the clients connected to the server.

e) Backup and recovery:

Generally a power full computer is used as a server and it is placed in highly secured place and a good mechanism in also implemented for backing up of critical data . If a client fells due to any reasons then such clients can easily restore their data through the server.

Disadvantages of computer network:

a) Security issue :

It is a major problem associated with computer network. If a computer is interconnected in a network then hacker can hack our confidential data that means they can steal our documents. however different security mechanism are implemented in the system to prevent such activities.

b) Repaid spread of viruses:

If a computer in a network is affected by computer viruses then their is a possible that of other system affected antiviruses are installed in the system to prevent from viruses.

c) Expensive initial setup cost:

The cost of networking depends on networking depends on the number of computer's connected. Different kinds of networking devices such as NIC card ( Network Interface Card), Routers, hubs, cables etc. are required for networking . Such devices are expensive which add sup total of networking.

d) Required skilled manpower:

A highly skilled technical manpower called administrator is required to established to operate, maintain a computer network and such manpower are not easily available in underdeveloped countries like Nepal and are also highly payable.