Tagged Questions
2
votes
0answers
77 views
Are there any secure commutative ciphers?
This answer lists two commutative cipher algorithms - Pohlig-Hellman and SRA. However, they don't appear to be too secure.
My question is, here there any commutative ciphers out there that are secure ...
0
votes
2answers
143 views
-4
votes
2answers
198 views
Why is there a strong distinction between stream and block ciphers?
If I don't err, in the literature a stream cipher is one in which each plaintext bit is processed individually, commonly via xor-ing with one bit of a random or pseudo-random bit stream, while a block ...
6
votes
2answers
693 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 ...
4
votes
3answers
766 views
Are there any simple and yet secure encryption algorithms?
Being very new to C++ and cryptography, I finally managed to implement a version of the Vinegere algorithm. I would like to try something a bit more complicated. I have looked at AES and DES and ...
1
vote
3answers
664 views
Does encrypting twice using the same block cipher produce a security weakness?
If I use the output of a cipher, for example a block cipher such as AES and encrypt it again with the same algorithm, I read that this introduces weaknesses into the overall security of the system.
...
9
votes
2answers
1k views
Why use an Initialization Vector (IV)?
Why use an Initialization Vector (IV)?
How are IV's used?
What are the advantages/disadvantages of using an IV?
Why use an IV instead of a longer key in which some section of the key is pubic?
What ...
