networks

networks

1. disadvantages

   • networks are expensive to set up
   • problems such as viruses can affect every computer on a network
   • expertise is needed to maintain and set up a network

2. advantages

   • share files so the same files can be accessed whichever computer you are on
   • 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

3. types of networks

   • LAN
     • local area network
       • a network in a small area or single organisation
   • WAN
     • wide area network
       • a network that spans a large area or multiple organisations

4. topologies

   • bus
     • cheap to install
     • high chance of catastrophic failure
     • lots of collisions
     • slows down as more computes are added
   • ring
     • cheap to install
     • no collisions(fast)
     • high chance of catastrophic failure
     • difficult to expand
   • star
     • low chance of failure
     • no collisions
     • expensive
     • depends on a switch

5. IP addresses

   • unique value, assigned to each device on a network
   • there are more devices on the internet than able to assign a unique address to.
   • unique addresses get assigned to each business/house
   • each house/business runs its own mini-network with different ip addresses
   • like home addresses but for devices

6. internet

   • the internet is a mesh topology
     • this is helpful because if one computer fails, there are other available paths.
   • large files are sent in packets, once they reach their final destination, they reassemble
   • routes between nodes are chosen by a route finding algorithm
     • route-finding algorithms find the lowest costing route between two nodes