All Questions
Tagged with symmetric stream-cipher
31
questions
2
votes
1
answer
361
views
Deriving secret keys vs generating and encrypting them
Suppose one has a password manager, based on symmetric cryptography, that requires a master passphrase to be unlocked. Argon2 is used for deriving a secret key from the master passphrase.
I need ...
- 123
1
vote
1
answer
329
views
Age: stream cipher with public key cryptography?
I have some rudimentary cryptography knowledge but am by no means an expert.
I generally understand stream ciphers, such as such as ChaCha20-Poly1305, to be symmetric. I am wondering how age (https://...
2
votes
1
answer
145
views
Sponge Duplex authenticated encryption with nonce reuse or no nonce
With a Sponge permutation in a Duplex construction for authenticated encryption.
illustration example: ascon; actual interest if relevant: keccak
Suppose there is no associated data and there is no ...
- 33
3
votes
3
answers
1k
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How to interpret my professor's statement about "seed" and "symmetric-key encryption"?
In the cryptography course, the professor said that:
these days for symmetric key encryption, instead of sending out the key, Alice sends the seed to Bob, and then based on that Bob can get the key.
...
- 43
3
votes
0
answers
329
views
Encrypt/Cipher and Decrypt/Decipher a string with a secret
In developing an app I have a simple use case in where I want to encrypt/cipher a string (it could also be a couple of bytes because it's essentially just an IP-Address). On the output I think it ...
- 131
1
vote
1
answer
109
views
Getting the plaintext encrypting the ciphertext
Context: an encryption game from overthewire (the link to it: https://overthewire.org/wargames/krypton/krypton6.html, also good for more info) where given the ciphertext, one must obtain the plaintext....
- 11
3
votes
1
answer
99
views
Number of keystreams generated in Kreyvium for a single key/IV pair
Kreyvium employs 128-bit key and 128-bit IV. By a single initialization procedure using a key/IV pair, how many keystreams can be generated?
- 31
3
votes
1
answer
936
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Which is the best algorithm for large scale file encryption other than AES?
I've been looking for a fast, powerful and robust algorithm for encrypting large files with authentication .
I would like to implement the algorithm on my own without using third party software. I've ...
- 1,030
3
votes
1
answer
302
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Does anyone sell a proprietary symmetric encryption alogirthm?
I know that the majority of people use standardized encryption ciphers such as AES-256, and for good reason. But what I want to know is if anyone has come across a company or organization that is ...
- 31
-1
votes
2
answers
908
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Are all block and stream ciphers symmetric?
I'm trying to categorize my knowledge. Can I place block ciphers and stream ciphers under symmetric with RSA/DH under asymmetric?
- 511
2
votes
3
answers
4k
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What is the advantage of CFB over OFB?
I was wondering if CFB can be better than OFB in any ways. I would like to know in what cases one would use CFB over OFB.
- 123
4
votes
0
answers
246
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Safely using ciphers that take small key sizes
Is it feasible to use triple encryption for block ciphers with the maximum keysize being the only significant security issue? I mean $C = E_{k_1}(E_{k_2}(E_{k_3}(P)))$ and $P = D_{k_1}(D_{k_2}(D_{k_3}(...
- 15.4k
0
votes
2
answers
3k
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XOR and cipher stream
I am new to cryptography and I am very confused. In fact, I am so confused that I have trouble providing a suitable title for my thread...
I know that a Substitution Cipher is designed to substitute ...
1
vote
2
answers
809
views
OTP stream cipher
I am new to cryptography, and there is one thing that is bothering me. I hope you can kindly help me to understand.
Let's imagine an attacker harvests the plaintext as well the ciphertext from a ...
- 21
2
votes
2
answers
6k
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What is the difference between a Stream cipher and a Symmetric Encryption algorithm?
According to the Tag definitions:
Stream Cipher: A stream cipher is an encryption algorithm which encrypts arbitrary length plaintext, using a key. Some stream ciphers generate a keystream from only ...
- 983