Computer Networks

Computer Networks

1. WAN and LAN

   • LAN
     • Local Area Network
     • A network contained in a single geographical area
   • WAN
     • World Area Network
     • A network that is accessed anywhere in the world

2. Disadvantages of Networks

   • Expensive-Extra hardware and wiring needed
   • More room for error-If something goes wrong it can affect the whole network
   • Difficult-It requires technical expertise
   • Malware-Viruses and other malicious software can spread throught the network

3. Advantages of Networks

   • Share files-So the 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
   • Advantages of Networks in Buisnesses
     • Only employees can access company data
     • It is easier to transfer files

4. Topology

   • Ring Topology
     • Clients are connected to eachother in a ring
     • Each client receives a message, if they are not the intended recipricant they forward it to the next client in the ring
     • Cheap to install
     • No collisions
     • Difficult to expand
     • High chance of catastrophic failure (a break in the central cable takes out the whole network
   • Star Topology
     • Clients are connected to a single switch and are expanded outwards
     • Easy to expand
     • Low chance of collisions
     • Low chance of catastrophic failure
     • Failure of the switch will take down the whole network
   • Bus Topology
     • A network that consists of a single cable that runs through the network
     • Cheap to install
     • High chance of catastrophic failure (a break in the central cable takes out the whole network)
     • High chance of collisions
     • Easy to expand

5. IP Addresses

   • Each computer in a network is assigned an IP Address to identify them
   • Internet Protocol Address
   • 32-Bit Binary Unit
   • There are not enough IP Address to individually assign one to each client

6. Packets

   • Packets are parts of data that are taken apart and re-assembled through a mesh
   • Packets can be disfigured when going the the mesh