Networks

Networks

1. Advantages

   • You can access your account from any computer connected to the network
   • Makes it much easier to share files and resources

2. Disadvantages

   • Networks are vulnerable to viruses and hackers
   • Can be very costly to set up all the hardware
   • Can be very hard to set up and maintain

3. Types Of Network

   • WAN
     • Wide Area Network
       • A large network that spans over several countries or organisations
   • LAN
     • Local Area Network
       • Only spans across one geographical location

4. Topologies

   • Bus
     • Lots of computers set up in a line that is all connected to one main wire
       • Cheap
       • High chance of collisions
       • High chance of catastrophic
       • Slows down as more computers are added
   • Star
     • Main switch in the centre with all the other computers connected to it
       • Fast
       • Easy to add more
       • Expensive
       • Failure on the switch will shut down all computers
   • Ring
     • Lots of computers set out in a ring formation
       • Cheap
       • No collisions
       • High chance of catastrophic failure
       • Difficult to add more

5. IP Addresses

   • Definition
     • IP Addresses are unique values assigned to every computer/device on a network, used to identify it
   • What is it for?
     • Messages on a network have an IP Address attached, which is how a computer knows whether or not to keep a message.
   • What does one look like?
     • It looks like a lot of numbers divided into pieces by dots.
       • 86.188.242.210
   • How many IP Addresses are there?
     • There is 4,228,250,625 different possible combinations

6. Internet

   • The routes are chosen by having the lowest 'cost' from its current location
   • Large files are sent in smaller packets and are then reassembled at the destination
   • Mesh Topology
     • All the computers are in no specific arrangement or order