Unit 1.5 (Network Topologies Protocols and Layers)

Unit 1.5 (Network Topologies Protocols and Layers)

1. Networks

   • A computer network is a number of computers linked together for them to share resources
   • Mesh Network
     • Where some or all workstations are directly connected to each other
   • Star Network
     • Each device is connected by a individual cable directly to the server

2. WiFi

   • Wireless Frequency
     • Radio waves are used to transmit data packets without the need for wires
   • WiFi is slower and more vulnerable to attack but it removes the need of cabling and networks
     • Can be set in remove places such as a plane, park, car etc

3. Encryption

   • It is a method of scrambling data with a key code which makes no sense
   • On a public WiFi network anyone can join and sniff out packets of data from other users
     • This is why encryption is used, the intercepted data will have no meaning

4. IP Address

   • A unique string of numbers separated by full stops that identifies each computer using the Internet Protocol to communicate over a network
     • 192.168.1.34
   • Each device on the internet has an unique IP address which is sent with the packets to identify which computer to send the data to

5. Protocols

   • Network protocols are a set of rules or conventions which control the communication between devices on a network

6. MAC Address

   • Identifies a device on a network by identifying the network adapter that the device is using
     • AA-34-G4-44-23-F1
       • It uses hexadecimal as a number base
       • It can not be changed
         • It is made when manufactured

7. Packet Switching

   • If you want to email a photo, it is broken down into small packets of data
     • Each packet is each given a header which contains the IP address of the network device it is being sent to, the header also contains the packet numbers
       • When the packets arrive at the destination the packets is used to reassemble the data