Topic Progress

Computers need rules on how to send and receive binary

  • the format of data packets
  • the addressing system
  • the transmission speed
  • error checking procedures


  • Ethernet
  • Wi-Fi: connect via wireless LAN and Wireless Access Point (WAP)
  • TC/IP: TC how messages are broken into packets. IP protocol for location of the device on the Internet
  • UDP: an alternative to TCP and uses datagrams to transmit messages. Has no error checking or correction
  • HTTP: accessing and receiving webpages in the form of HTML
  • HTTPS: encrypts data and is more secure (used on e-commerce site)

Email Protocols

  • IMAP: stores email on server but allows users to view and manipulate as though stored locally
  • POP: downloads email from server then deletes from server
  • SMTP: used for sending out and forwarding email SMTP >>>>>>>


TCP/IP model consists of 4 layers. The advantage is that it is easier  for suppliers such as Microsoft to adapt software to specific hardware

  • Application:
    • HTTP
    • HTTPS
    • FTP
    • IMAP
  • Transport:
    • TCP
    • UDP
  • Network/Internet
    • packages and routes data
    • TCP
    • UDP
  • Link:
    • hardware NIC is located
    • Attaches to MAC adresses of the sender and the recipient

Some tests to help you memorise the concept of layers. Scroll down to hide previous test.

Layers 1

Layers 2

Layers 3