1.4 Wireless and Wired Network

1.4 Wireless and Wired Network

1. LAN

   • Local Area Network
   • Computers connected together over a small geographical area
     • A building
     • Home
     • School
   • Own infrastructure and network hardware due to distance and pracicalities

2. WAN

   • Wide Area Network
   • Computers connected together over a large geographical area
     • Several buildings/sites
     • Town
     • County/Country
   • Uses external hardware and external infrastructure e.g. use of The Internet and Satellites

3. Internet + WWW

   • Accessible, store and look things up on there
   • World Wide Web
     • Isn't accessible
     • Files, programs and websites
   • Infrastructure
     • Raters
     • Servers and hardware

4. Client-server

   • Provides all services on the network through a central computer
   • Network relies on central computer
   • Clients requires sevices from the server
   • Expensve to build and maintain
   • Requires a dedicated network manager

5. Peer to Peer

   • Cheap to set up and computers are needed to be maintained individually
   • All computers have equal status
   • No additional hardware required
   • Each device can act as a client and server

6. Keywords

   • Packet
     • Data transmitted over a network is broken down into packets
     • Contains the IP address of the sender and reciever
     • Contains a sequence number (A certain life time on the internet)
   • WAP
     • Wireless Access Point
     • Has wires connected to the point
     • Allows a person to access the internet/network wirelessly
     • Part of the internet
   • Network performance
     • The speed of the message which can be sent or a document can be retrieved
     • Affected by the number of devices on the network or of the bandwidth transmission medium
   • Transmission media
     • A pathway that carries the information from sender to receiver by cable, wires or electromagnetic signals

7. More keywords

   • Hub
     • Can only work with one device at a time
   • Router
     • Acts as a switch and WAP
   • Switch
     • Works with a lot of devices at the same time