Introduction to networks

Introduction to networks

1. Types of networks

   • wan
     • (Wide area network) wan is a connection of LANs to extend a network over larger geographical location
   • Lan
     • (Local Area Network) lan is a network that is specific to one area only. Multiple of these are interlocked to create a wan.

2. Disadvantages of networks

   • Expensive
     • Wiring and hardware are required and can be expensive
   • More room for error
     • It can affect other computers
   • Difficult
     • It requires technological expertise
   • Malware
     • It brings viruses and worms into the network.

3. Advantages to networks

   • Share files
     • The same files are available every where you go
   • Share resources
     • such as printers and internet connection
   • Share Logins
     • The same username and password on every computer

4. Topology

   • 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
   • The arrangement of computers on a network
   • 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. What is an IP Address

   • An IP address is a unique value assigned to every computer on a network
     • Each one has a 32- bit value
     • In Binary we convert each part in decimal 8 bits