1.5 Network Topologies, Protocols and Layers

1.5 Network Topologies, Protocols and Layers

1. A Mesh network is where some or all of the work stations or other devices are directly connected to each other. Most are usually connected to the node that they exchange the most data with

   • A Star network is, each device by an individual cable directly to the server. star networks are usually the layout of choice in schools and offices because they tends to be the most reliable of the Topologies
     • Advantages: very reliable and easy to add additional devices
       • disadvantages: use of switch can increase the cost of network. additional devices restricted by central device

2. WiFi is wireless frequency - radio waves are used to transmit data packets without the need for wires

   • this method is slower to use and more vulnerable to attack but it removes the need for cabling and networks
     • this means that it can be set up in remote locations such as in vehicles, in parks or planes etc.

3. Encryption is a method of scrambling data with a key code which makes no sense

   • on a open or public WiFi network anyone can join and sniff out packet sniff data from other users
     • therefore Encryption is used. if intercepted the data will have no meaning.
       • in order to read the data the user is required to decrypt the data using the key

4. Key words

   • Encryption
   • WiFi
   • Eternet
   • Star newtrok
   • Mesh network
   • Topology

5. when you are using a secure site for example your bank, purchasing on Amazon, encryption applied to keep your details safe

   • the encryption method used is called 'SSL' (Secure socket layer)
     • a tiny padlock appears in your browser window, usually on the left hand side of the address bar and the website address starts with 'HTTP'

6. A MAC address is permanent

   • An IP address will change and is not permanent

7. HTTP - Used by web browsers to communicate with web servers

8. IMAP - used to retrieve emails

9. SMTP - used to send emails

10. static IP address never changes

11. Dynamic IP address will change

12. FTP - File transfer protocol

13. POP - Post office protocol

14. POP3 - Post office protocol version 3

15. The purpose of POP3 is that it retrieves emails and cannot send emails