AQA 7517 4.9.3.1: The Internet and how it works
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 (F10.5 and F10.6) you learned that data is split into packets, that the Internet is a network of networks, and that DNS turns names into IP addresses. At A level you need the detail: what exactly is in a packet, what a router decides and how, how a gateway differs from a router, the parts of a URL, and the chain of servers a DNS lookup really visits.
- Packet switching
- Routers and gateways
- The Internet's addresses
- DNS
Or do it in the simulator, with tasks that mark themselves
Lessons that teach it
- A12.3 How the Internet works Networks and the web
Packet switching, routers and gateways, URLs, fully qualified domain names and DNS. - 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 A12.3 How the Internet works, running here. Change the program and press Run.
The specification is AQA's own document; this page says which of our lessons teach point 4.9.3.1 and is not endorsed by the board.