introduction to networks

introduction to networks

1. disadvantages

   • EXPENSIVE- extra hardware wireing needed
   • MORE ROOM FOR ERROR- if something goes wrong it will affect every other computer
   • MALWARE – viruses and other malicious software can spread through the network
   • DIFFICULT -it requires a technical expertise

2. 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

3. 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

4. networks

   • A network is a group of computers connected together so they can communicate

5. Network Topologies

   • Network Topology is the arrangement of computers and other elements of a network
   • Bus
     • The network consists of a single cable that runs through the network
     • All devices attach to this single cable
   • ring
     • Computers are connected to each other in a ring
     • Communication only goes in one direction
     • Each computer receives a message, and if it is not the intended recipient, passes it on to the next computer
     • No central cable, each connection is between two computers
   • star
     • All computers are connected to a central switch.
     • All computers are connected to a central switch.

6. disadvantages + disadvantages of network topologies

   • Bus
     • advantage:: 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
     • disadvantages: Expensive (needs a lot of cabling, and a central switch, which is expensive). Failure of the switch will take down the network .
     • 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).

7. network addressing

   • ip adress
     • An IP Address is a unique value assigned to every computer on a network, used to identify it
     • messages on a network have an IP address attached, which is how a computer knows whether or not to keep the message