Tagged Questions
6
votes
2answers
718 views
Why do block ciphers need a non-linear component (like an S-box)?
Why is there a requirement of "Non-Linear functions" as a component of many popular block ciphers (e.g. the S-box in DES or 3DES)?
How does it make the cipher more secure?
The only intuition I have ...
5
votes
3answers
652 views
Security of simple xor and s-box cipher?
What weaknesses (or strengths) do block ciphers based on only key xor and s-box have when operating in CBC mode?
A cipher's internal primitive might be a simple as this:
$C = S[M \oplus k]$, where ...
7
votes
1answer
458 views
Replacing the Rijndael S-Box?
The Rijndael S-Box design generates a permutation cycle of type $2+27+59+81+87$. What effect would replacing that permutation with a cycle of type $256$ have on the security of AES?
