Edexcel 1CP2 5.3.2: Protecting digital systems
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
Data travelling across a network can be intercepted (lesson F11.4). Encryption makes that harmless: it scrambles the data so that only someone with the key can read it. Intercepted, it is gibberish. This lesson builds a cipher, sends a secret message to another robot, and explains how the whole web is kept private.
- The idea
- The Caesar cipher
- Symmetric and asymmetric
- A secret over the radio
Or do it in the simulator, with tasks that mark themselves
Lessons that teach it
- F11.6 Encryption Cyber security
Plaintext, keys and ciphertext, the Caesar cipher, symmetric and asymmetric, and a secret over the radio. - F11.8 Writing secure programs Cyber security
Validating input, access levels in code, and testing for security.
Try it on a robot
The task from F11.6 Encryption, running here. Change the program and press Run.
Past paper questions on this
Real exam questions that test this, each worked through with a program you can run.
The specification is Edexcel's own document; this page says which of our lessons teach point 5.3.2 and is not endorsed by the board.