Computer Networks

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compter networks connect lots of computers together so that they all have the programs that the main program has.Computer networks provide a naturally redundant environment of computer resources that are connected using proven communication protocols and reliable, high speed media.

Peer-to-peer

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a peer-to-peer network is A small network where each computer has equal status and control. this network relies on the computing power and bandwidth.

simple to program.

reduced cost.

each server nna serve as the admin.

they are less secure than server clients.

speed can decrease if there are too many computer connected.

Client server

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The client server architecture consists of client computers such as PCs sharing resources such as a database stored on a more powerful server.the computers connect to the server are called the clients.these networks have intranets(Inter-connected network within one organization that uses Web technologies) and extranets(An Internet based access method to a corporate intranet site by limited or total access through a security firewall.)

Client servers can connect a lot more servers than p2p.

Client servers have a single super computer that connects all the computers together so if the server has a program they all do.

Client servers are more secure than p2p as there is only 1 server controlling the computers

If ther server computer fails then all of the other computers are likelt to fail

The server can overload

A client server is more expensive and tricky to set up than p2p.

LAN(Local Area Network

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local area network is a neteorks that is local to the main server.A network connecting a number of computers to each other or to a central server so that the computers can share programs and files.in a LAN two or more computers are phsically connected which is simailar to a network at home.

Files can be stored on the central computer

Files can be backed up more easily

Users can easily access there infomation or work from any of the workstations

The system can be open to hackers so viruses are possible

They have a linited range and can be expensive

It could degrade in performance so can be costly to be repaired

WAN(Wide Area Network)

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A WAN connects LANsand MANs over great distances, such as across the country and around the world.A computer network that spans a long distance ie between cities or countries. Covers an area larger than a LAN or a MAN

By siting at one city.country the user can access there data from there home computer on the other side of the world

the user can print a document or send an instand message in 1 mouse click

can use online software for comunication

if the one network gets a virus then your computer may get this

the more computer there is the more chance of hackers getting access to the system

can be expensive to install and maintain

MAN(Metropolitan Area Network)

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A high speed network designed to link together sites in a metropolitan or campus area. The IEEE has defined its 802.6 standard for MANs based on the Distributed Queue Dual Bus technologyA network that covers one geographic area ie a city or a campus. Covers a larger area than a LAN but a smaller area than a WAN

Connects a large area.

Connects both public and private industries

Is cheap to communicate with somebody across the world

MAN is very complicated

Much more expensive to istall than LAN or WAN

The larger area coverage might lead to connection speed being reduced