Networks

Networks

1. advantages

   • Share files, so the same files are available whichever computer you use
   • Share resources such as printers and the internet connection
   • Share logins, so the same username and password can be used on every computer on the network

2. Disadvantages

   • Cost: networks are expensive to set up
   • Increased risk: problems such as viruses can affect every computer on the network
   • Difficulty: experties are needed to set up and maintain a network

3. Types of network

   • 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
     • Advantages
       • Cheap to install
     • Disadvantages
       • High chance of catastrophic failure
       • Lots of collisions
       • Slows down as more computers are added
   • Star
     • Advantages
       • Low chance of failure
       • No collisions (fast)
     • Disadvantages
       • Expensive
       • Depends on a switch
   • Ring
     • Advantages
       • Cheap to install
       • No collisions (fast)
     • Disadvantages
       • High chance of failure
       • Difficult to expand

5. IP Address

   • its a unique value assigned to every computer on a network used to identify it.
   • The schools IP address is: 1010110. 10111100. 11110010. 11010001
   • The internet is a huge network with more devices than its possible to assign a unique address to. Unique addresses are assigned to businesses and houses. These businesses and houses run there own mini network inside with different IP addresses.

6. Internet

   • The internet is a giant mesh of computers. There are multiple different routes between any two nodes.
   • a cost is assigned to each connection in the mesh. route finding algorithms are used to find the lowest cost route between two nodes,.
   • data is split into small chunks called packets. each packet is sent along the lowest cost route