Networks

Networks

1. Disadvantages

   • Increased Risk
     • If one computer gets a virus, it will spread to the other computers.
   • Difficulty
     • Expertise is needed to set up and maintain a network.
   • Cost
     • It is expensive to set up a network.

2. Advantages

   • Share resources
     • All computers will be connected to the same printer / internet.
       • (By connecting just one)
   • Share logins
     • If you log in on one computer, you can log in on all of the others.
   • Share files
     • The same files will be on every computer connected to 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. Topology

   • Ring
     • Disadvantages
       • Difficult to expand.
     • Advantages
       • Cheap to install
       • No collisions
         • Everything goes one way
   • Star
     • Disadvantages
       • Expensive
         • Many cables are used to connect it to a switch / hub.
         • The switch also costs a lot.
       • Failure of the switch takes down the network
     • Advantages
       • Fast
         • No collisions
       • Low chance of catastrophic failure.
   • Bus
     • Advantages
       • Cheap
         • Just one cable
     • Disadvantages
       • Slow when too many computers are added
         • Collisions
       • High chance of catastrophic failure
         • Only one cable - if it breaks everything goes down.

5. IP addresses

   • An IP address is a unique value assigned to every computer in a network which is used to identify it.
   • Since there aren't enough IP addresses for all devices on the internet, each house / business has their own unique adress.
     • Each device in this network then has it's own IP address.
   • IPv4
     • There are just over 4 billion unique IP addresses.
     • it can go from 0,0,0,0 to 255,255,255,255
   • IPv6
     • There are almost 80 octillion unique addressed, being more than enough.
     • It uses 16 bits for each part of the address.