Computer Networks LAN WAN MAN

Computer Networks LAN WAN MAN

Computer Networks LAN WAN MAN

Defination:

A network can be formed When number of computers connected together to share information and resources through some physical media.that media may be guided or unguided.

Description:

Computer network play an important role in our daily and practical life.In some organization we need to share resources like printer , hard disk, scanner and even programs.for attaining this purpose we have to form a network.Nodes are connected together by using any types of media . That media may be guided like twisted pair, coaxial,fiber optic or this media may be unguided like radio waves etc.
Network criteria:
A network must need to satisfy these criteria .Otherwise it ‘ll not considered a network.
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Responsive

A good network be responsive to all the resources at all the time.It musty to satisfy all the request from all the resources within a network.
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Consistency

A network must be consistent.When consistency is not maintained then network may lost his worth.
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Security

Basic purpose of a network is to share information and resources ,if that sharing is not secure then this make the network useless.So security is an important criteria for a network.

Types of Computer networks:

Computer networks are categories in different types on the basis of coverage ,speed and functionality.Major computer networks are as below:
• LAN(Local Area Network)
• MAN(Metropolitan Area Network)
• WAN(Wide Area Network)
• PAN(Personal Area Network)

LAN

LAN stands for local area network.It is a network that connects computers and devices in a limited geographical area,that are closely positioned together.
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Node

Each computer or device on a network is called a node.they often share resources such as printer,large hard disk drives, and programs.nodes are connected together through wires.
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Wired LAN

The LAN that is connected through some physical media such as twisted pair ,coaxial or fiber optic cable.
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Wireless LAN

The LAN that uses no physical wires.Computers and devices that access a wireless LAN Must have built in wireless capability or the appropriate wireless network card,or other wireless device
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Distance coverage

LAN provides Limited coverage, about upto 2 miles or 2500 meters.
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Speed of operation

LAN provide high speed .typically 10 ,100 and 1000Mbps.
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Technology used for medium

Locally installed, twisted pair, fiber optic cable, wireless
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Applications

Used mainly by fixed desktop computers and portable computers (e.g. laptops) . Now-a-days it is used by smart phones due to emergence of WLAN network
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Example

Network that form in an office,computer lab, or in an organization.

Pros/ Benefits/ advantages of LAN

• Resource sharing:
• Communication
• Data security
• Internet access sharing

Cons/ Disadvantages of LAN

Data security concerns
Time consuming
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