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TYPES OF COMPUTER NETWORKS:
A computer networks is a communication system connecting two or more computers that work together to exchange information & share resources. A network may consist of microcomputers or it may integrate microcomputers or other devices with large computer. Networks can be controlled by all nodes co-ordinarily & supply all resource. These networks differ in geographical size. There are three important types of networks.
1. Local Area Network
2. Metropolitan Area Network
3. Wide Are Network
1. Local Area Network:
A computer is connected to other computer with cables and other means & make communication possible between them is called network. The network, which connects one or more computers within a limited distance of one another perhaps within the same building or within the same office premises, is known as Local Area Network. This requires special software NetWare, LAN Cards (Ethernet Card), cables and connectors etc required for connecting computers included in it. Many organisations need multi-user environment, which allows sharing of data as well as expensive resources like printers and storage. Following figures shows the multi-user system, which includes LAN. A local Area Network is a system of interlinked personal computer, sharing common resources, like disks, printers etc. These networks are widely used now days.
LAN used for following purposes
1) Data processing: Data entry transaction processing (Banking system0, File transfer, Inquiry/response.
2) Office Automation: Document/word processing, Electronic mail, Intelligent copying.
3) Factory Automation: CAD/CAM, Inventory control/order entry/shipping, Monitor and control of factory floor equipment
4) Process control
5) Fire & Security: Sensor alarms. Cameras and monitors.
6) Telephones, Teleconferencing.
Metropolitan Area Network: (MAN) These networks are used as links between office buildings in a city. Cellular phone systems expand flexibility of Manes by allowing links to car phones and portable computers.
WIDE AREA NETWROK: (WAN) Wide area Network is a countrywide and worldwide network. Among other kinds of channels, they use microwave relays and satellites to reach users over long distances – for e.g. from Los-angels to Paris. The widest of all WANs is the Internet, which spans the entire globe. The primary difference between a LAN, MAN and WAN is geographical range. Each may have various combinations of hardware, such as microcomputers, minicomputers, mainframe computers and various peripheral devices.