COMPUTER PLATFORMS

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COMPUTER PLATFORMS
Networking Fundamentals Week 6
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Week 5

• What is a network?
• What does the network do?
• Why network?
• Common network types
• Network architecture
• Client/Server
• Peer-to-peer
• Network Components

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Whats a network?

• Technology used in communication systems
• Telecommunications
• Digital Broadcasting
• Data Communications
• It is
• Mobile phones, telephones
• Computer networks, the Internet
• Facsimile (FAX)
• TV and Radio

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Whats a network?

• A collection of systems / resources which are all
  connected together via a medium
• Cables
• Lots of different types
• E.g.- Public telephone network
• Wireless
• Different frequency ranges
• E.g.- Mobile phone networks
• The medium is used to send signals between two
  communication point
• Computer data is translated into signals to be
  sent / received over a medium

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What does the network do?

• Allows people in remote locations to talk with
  each other
• Or at least, allows their computers or
  communication equipment to talk
• Promotes the sharing of
• data
• resources
• ideas
• media (e.g.- images, audio, video)

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Why network?

• In the office
• The Internet
• Email, web, FTP, e-business, etc.
• Sharing of local information
• Communications
• Sharing resources
• Printers, scanners, plotters, etc.
• At home
• The Internet
• Email, web, FTP, P2P sharing, news, etc.
• Sharing resources
• Printers, scanners, etc.
• Ease of communication for more than one PC

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Common Network Types

• LAN (Local Area Network)
• Connect together computers in the same room or
  building
• E.g.- NEWI Network
• WAN (Wide Area Network)
• Connects together computers of large geographical
  or geological areas
• E.g.- The Internet, JANET
• MAN (Metropolitan Area Network)
• Connects together buildings or sites over city /
  town sized areas
• 2 6 Km apart

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Computer Network Architecture

• Client / Server
• Centralised Control / Administration
• The SERVER(s)
• They provide a service or services to users
• Will almost always control the network
• Could provide email, file sharing, web services,
  etc, to users
• CLIENTS
• These could be computers or dumb terminals
• Connect to the server which provides information
  or services
• Are controlled and administered by the server
• If server has a fault this affects the clients
  connected
• Common in business

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Computer Network Architecture

• Peer-to-peer
• Everybodys Equal
• Essentially allows users to both send and
  retrieve files from each others computers
• Like having a Client and Server on each machine
• On the Internet this often refers to file sharing
  applications
• Such as Napster, AudioGalaxy, Gnutella, etc.
• Lacks any central control
• Can compromise security
• Used in small businesses and at home

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Network Components

• Node
• Terminal
• Computer
• A device connected to the network
• Network Interface
• Connects the node to the physical network
• Network Interface Card (NIC) on LANs
• MODulator / DEModulator (MODEM)
• Hub
• Sometimes called a concentrator
• A central point where network connections from
  nodes meet
• Depends on topology

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Network Components

• Media
• The object over which a signal is transmitted or
  received
• The thing which interconnects two or more points
• Cables and wires
• Coaxial cable
• Twisted pair cable
• Fibre optic cable
• Wireless
• Microwave
• Satellite
• Infrared

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Week 5 What do you know?

• What a network is
• What a network does
• Communication
• Sharing of resources
• Common network types
• LAN, WAN, MAN
• Network architecture
• Peer-to-peer
• Client/Server
• Network Components
• Nodes
• Network Interfaces
• Hubs
• Media