Networks lesson mindmap

Networks lesson mindmap

1. Advantages

   • You can share files, so the same files are available on every computer
   • You can share logins, so the same username and password can be used on every computer
   • You can share resources such as printers and internet connection.

2. Disadvantages

   • It is costly. Hardware and wiring is needed.
   • If something goes wrong, it can effect every computer. Viruses can spread through the network

3. Types of Networks

   • WAN
     • Wide Area Network
       • A network that spans a large geographical location or organisation
   • LAN
     • Local Area Network
       • A network that spans a small geographical location.

4. Network Topologies

   • A network topology is the arrangment of computers and other elements of a network
   • Bus Topology
     • Advantages
       • Cheap to install
     • Disadvantages
       • High chance of catastrophic failure
       • Lots of collisions
       • Slows down as more computers are added
   • Ring Topology
     • Advantages
       • Cheap to install
       • No collisions
     • Dis advantages
       • High chance of catastrofic failure
       • Dificult to expand
   • Star Topology
     • Advantages
       • Low chance of failure
       • No collisions
     • Disadvantages
       • Expensive
       • Depends on a switch

5. Network addressing

   • IP addresses
     • An IP address is a unique value assigned to every computer on a network, used to identify it.
     • Messages on a network have an IP address attached, which is how a computer knows whether or not to keep the mennage
     • The internet is a huge network with more devices that it's possible to assign a unique address to
     • Unique addresses are assigned to businesses and houses
     • These houses and businesses run their own mini-network inside with different IP addresses

6. The Internet

   • The internet is a giant mesh of computers
   • There are multiple different routes between any two nodes
   • It is impossible yo break the internet, since another route can always be found
   • A cost is assigned to each connection in a mesh
   • Route-finding algorithms are used to find the lowest costroute between two nodes
   • Data is split into small chunks called pachets
   • Each packet is sent across the lowest cost route
   • The packets are re-assambled on the other side