Networks

Networks

1. Disadvantages

   • Expensive – extrahardware and wiring needed More room for error – if something goes wrong it can affect every computer Difficult – it requires a technical expertise Malware – viruses and other malicious software can spread through the network

2. Advantages

   • Consistent User Experience - You can log on to any computer in the school using the same username and password Your files are available on every computer you use, even if you created them on a different computer You can print, use the Internet, email and use the same software on any computer

3. Types of networks

   • WAN
     • Wide area network
   • LAN
     • Local area network

4. Network topologies

   • BUS
     • Advantages
       • Cheap to install (only one wire needed)
     • Disadvantages
       • High chance of catastrophic failure (a break in the central cable takes out the entire network) High chance of collisions (multiple communications on the same cable that corrupt each other, slowing down the network) More computers mean more collisions, so the network gets slower as it gets bigger
   • RING
     • Advantages
       • Cheap to install (one cable per computer) No collisions - only one computer is transmitting on each cable
     • Disadvantages
       • High chance of catastrophic failure (if any cable breaks or any computer goes down, the entire network fails Difficult to add new computers
   • STAR
     • Advantages
       • Fast (low chance of collisions) Easy to add new computers Low chance of catastrophic failure (a broken cable only takes out one computer, the rest of the network is fine)
     • Disadvantages
       • Expensive (needs a lot of cabling, and a central switch, which is expensive) Failure of the switch will take down the network

5. IP Address

   • The IP Address is unique value assigned to each computer on a network. Each IP address on a network must be unique.
   • External IP
     • Outside your house
   • Internal IP
     • Devices inside the house