AQA A-level Computer Science (7517)Specification point 4.9.4.1

AQA 7517 4.9.4.1: TCP/IP

The free BugBot lessons that teach this point, a robot to try it on, and the past-paper questions that test it.

What it covers

At GCSE (F10.7 and F10.8) you named the four layers of TCP/IP and matched protocols to what they do. At A level you need to explain what each layer adds as data goes down the stack, how ports and sockets let one computer run many conversations at once, and how the standard application protocols are used, down to the commands a client sends.

  • Four layers
  • Ports and sockets
  • The application protocols
  • A packet of your own
Read the free lesson (30 min)

Or do it in the simulator, with tasks that mark themselves

Lessons that teach it

  1. A12.4 The TCP/IP stack and protocols Networks and the web
    The four layers, encapsulation, ports and sockets, and HTTP, HTTPS, FTP, SMTP, POP3 and SSH.
  2. A12.10 Project: a reliable link Networks and the web
    Receive a route as packets out of order, reject the damaged one, and drive it.

Try it on a robot

The task from A12.4 The TCP/IP stack and protocols, running here. Change the program and press Run.

The specification is AQA's own document; this page says which of our lessons teach point 4.9.4.1 and is not endorsed by the board.