Networks

Networks

1. advantages

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

2. disadvantages

   • cost: Networks are expensive to set up
   • increased risk: problems such as viruses can affect every computer on the network
   • Difficulty: Expertise is needed to set up and maintain a network

3. types

   • WAN
     • Wide Area Network
     • a network that spans a large area or multiple organisations
   • LAN
     • Local Area Network
     • a network in a small area or single organisation

4. Topologies

   • bus
     • advantages
       • cheep to install
     • disadvantages
       • high chance of catastrophic failure
       • lots of collisions
       • slows down more as more computers are added
   • star
     • Advantages:
       • low chance of failure
       • no collisions
     • disadvantages
       • expensive
       • depends on a switch
   • ring
     • disadvantages
       • high chance of catastrophic failure
       • difficult to expand
     • advantages
       • cheep to install
       • no collisions
   • mesh
     • the internet is a giant mesh of computers
     • there are multiple different routes between any two nodes
     • its impossible to break the internet since another route is found

5. IP Adress

   • definition: a unique value assigned to every computer on a network, used to identify it
   • there is a total of 4228250625 IP Adresses in the world
   • the internet is a huge network with more devices than possible unique adresses
   • unique adresses are assigned to businesses and houses
   • messages on a network have an IP Adress attached, which is how a computer knows whether to keep a message or not

6. internet

   • data is split into chunks called packets
   • each packet is sent down the lowest costing route
   • the packet become whole on the other side