Cryptography

Learn the techniques to start you on your way to becoming a cyber security expert!

This Challenge introduces the basic cryptography concepts that impact the way we secure online communication.

In this Challenge students will learn about:

data representation,
how cryptography can be used to hide messages in images and sound,
problem decomposition and algorithms,
classic cryptographic ciphers like rotation, mixed-substitution and XOR,
techniques used to break these forms of encryption,
careers in the cyber security industry.

This Challenge is a part of the Schools Cyber Security Challenges series, developed by Grok Academy in partnership with ANZ, Australian Government: Australian Signals Directorate, AWS, BT, Commonwealth Bank, Australian Government: Department of Industry, Science and Resources, Fifth Domain, NAB and Westpac.

Your current score is: 0 points.

	Module	Progress
1.	Representing data	View Hidden message View What's the binary number? View What's the binary? View Numbers to Emoji View Find the coordinates View Secret meeting place View Trick Troll!
2.	Single key ciphers	View What is the secret key? View Order the tasks View Algorithm to shift letters View Encrypting messages View The mystery of decryption View What is the secret (XOR) key? View Mission XOR
3.	Frequency analysis	View Mixed substitution View Crack this sentence View Decrypt this song! View Analyse this song! View Location vigenère

Representing data

1.	View Hidden message	Hidden message You have not made any submissions.
2.	View What's the binary number?	What's the binary number? You have not made any submissions.
3.	View What's the binary?	What's the binary? You have not made any submissions.
4.	View Numbers to Emoji	Numbers to Emoji You have not made any submissions.
5.	View Find the coordinates	Find the coordinates You have not made any submissions.
6.	View Secret meeting place	Secret meeting place You have not made any submissions.
7.	View Trick Troll!	Trick Troll! You have not made any submissions.

Single key ciphers

1.	View What is the secret key?	What is the secret key? You have not made any submissions.
2.	View Order the tasks	Order the tasks You have not made any submissions.
3.	View Algorithm to shift letters	Algorithm to shift letters You have not made any submissions.
4.	View Encrypting messages	Encrypting messages You have not made any submissions.
5.	View The mystery of decryption	The mystery of decryption You have not made any submissions.
6.	View What is the secret (XOR) key?	What is the secret (XOR) key? You have not made any submissions.
7.	View Mission XOR	Mission XOR You have not made any submissions.

Frequency analysis

1.	View Mixed substitution	Mixed substitution You have not made any submissions.
2.	View Crack this sentence	Crack this sentence You have not made any submissions.
3.	View Decrypt this song!	Decrypt this song! You have not made any submissions.
4.	View Analyse this song!	Analyse this song! You have not made any submissions.
5.	View Location vigenère	Location vigenère You have not made any submissions.

Representing data

1.	Intro to crypto
2.	Binary Numbers
3.	Conventions
4.	Characters and ASCII numbers
5.	Hiding messages in images
6.	Hiding messages in audio

Single key ciphers

1.	Cryptographic keys
2.	Rotation ciphers
3.	Rotating past 'z'
4.	Decryption
5.	XOR, binary and representation
6.	Brute force attacks
7.	Congratulations!

Frequency analysis

1.	The evolving nature of cryptography
2.	A different way of encrypting text
3.	Patterns in words
4.	Frequency analysis
5.	Frequency analysis can also be beaten
6.	MFA