1.5 Network Topologies

1.5 Network Topologies

1. A network is a number of computers connected together to share resources:hardware software and data

2. WiFi

   • Cheap to set up
   • Can connect multiple people at once
   • Not stuck in a single position
   • Easier to hack
   • Signal reduces due to wall interference
   • Not stable connection due to 'drop off'
   • Radio waves transfer the packets of data
   • Can be set up in remote areas like cars planes or parks

3. Ethernet

   • Tied down to a single position
   • Can connect 1 device
   • Stable connections
   • Less chance of being hacked
   • Faster transfer speed

4. Encryption

   • Unscrambling data with a key code that makes no sense
   • On public wifi anyone can join so anyone take packets of data from others
   • encryption allows any taken packets to have no meaning
   • The person needs a key to decrypt the data
   • SSL is used when using bank sites, a padlock appears to secure data

5. IP Address

   • Unique numbers separated by full stops identifying the computers communicating on the network
   • Each device has their own IP address so they can be identified
   • IP Address have classes
   • indicates purpose of the network

6. Mac Address

   • Identifies differences in devices
   • embedded into device so cannot be changed
   • Built into the NIC
   • Made of 48 bits, mainly in hexadecimal

7. Protocols -set of rules that control communications between devices

   • TCP/IP
     • Transmission control protocol
     • Internet Protocol
   • HTTP(S)
     • Hypertext transfer protocol(Secure)
   • FTP
     • File transfer Protocol
   • POP
     • Post office Protocal
   • IMAP
     • Internet message access Protocol
   • SMTP
     • Simple Mail Transfer Protocol