computer network

COMPUTER NETWORK

A computer network means two or more than two computers connected with each other to share data , hardware,software,and other resources .Other resources includes printers,hard disk ,CD drive etc.Telephone lines ,cables,satellite links ,radio waves and other communication techniques, interconnect computer in the network.

ADVANTAGE OF THE COMPUTER NETWORK

• Computers in a network can access network-connected hardware devices like printers disk drives etc.


• Information can exchange rapidly in computer network.


• Computers in a network system share different software packages .


• Data in a network environment can be updated from any computers .Updated data can be accessed by all computers of the network.

DISADVANTAGES OF COMPUTERS NETWORK

• Failure of server stops application being available.


• Network failure cause loss of data.


• User work dependents upon network.


• System opens to hackers.

NETWORK CATEGORIES On the basis of the size of the network, the distance it covers and the type of the line used in communication , the computers network is divided into three categories .They are;

1. Local Area Network


2. Metropolitan Area Network


3. Wide Area Network
   

1.LOCAL AREA NETWORK

A local area network (LAN) is a network of computers that are relatively near with each other and are connected in a way that enables them to communicate by cables and a small wireless device.A LAN can consist of just two or three computers to exchange data or share resources or it can be include hundreds of computers of different kinds.Any network that exists with in a building ,or within a short distance is considered as LAN.

Features of local area network

• The diameter is not more than a few kilometers.
  
• A LAN offers bandwidth of 10 to 100 Mbps.


• It is controlled by a single organization.

2.METROPOLITAN AREA NETWORK

A Metropolitan area network (MAN) is a network of computers with spreed over metropolitan area such as with in city.It connects two or more LAN together.A single organization or a group to share data and resources may operate MAN .ISP providing network communication within a city and the network communication with in a city and the network of different branches of a bank with in a same city are the examples of the MAN.

Features of Metropolitan Area Network

• it covers a limited geographical area .
• it may be owned by single or multiple organization.
• it uses cable or wireless connections.
• it uses private or public connection medium.

3.WIDE AREA NETWORK

A wide area network (WAN) is a network system of connecting two or more computers generally across a wide geographical area such as cities ,district and countries.This type of network uses i telephone lines ,satelite links and other long-range communication technologies to connect computers .

Features of Wide Area Network

• it covers a large geographical area.
• it is owned by multiple organizations.
• it uses public connection mediums such as telephone lines,wireless technology etc.