Year 11 Computer Science ATAR: Encryption basics and classical ciphers
Students learn why data is encrypted and how keys, Caesar ciphers, brute force and frequency analysis show what makes encryption strong or weak.
One content description from the full WA Computer Science ATAR Year 11 — Cyber Security journey. All 12 modules below are in that journey too, with the same content — add just these to a class, or the whole strand.
Modules (12)
1
Why data is encrypted
2
Plaintext
3
Ciphertext
4
Encryption key
5
Encrypting a message with a Caesar shift
6
Decrypting a message with a Caesar shift
7
Key space: how many keys a cipher has
8
Breaking a Caesar cipher by trying every shift
9
Frequency analysis
10
Why a Caesar cipher is weak compared with modern encryption
11
Base64 is encoding, not encryption
12
Encryption and decryption
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