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visits member for 2 years, 11 months
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I am an undergraduate computer science and mathematics student in New Zealand. My fields of interest are computer graphics, in particular the physics of light transport, and to some extent cryptography, as well as programming and software development in general.


Jan
31
revised How to best obtain bit sequences from throwing normal dice?
grammer!!
Jan
30
answered How to best obtain bit sequences from throwing normal dice?
Jan
30
comment How to best obtain bit sequences from throwing normal dice?
This previous question may be relevant.
Jan
30
comment Decryption a chunk of file with AES
You can do that, but you'll have to create individual MAC fingerprints for each chunk (or authenticate everything before) because unauthenticated data is worthless. Depending on the number of chunks, this may or may not be viable.
Jan
29
comment How do I derive the time complexity of encryption and decryption based on modular arithmetic?
@almodawan My comment assumed $n$ (or $N$) is the modulus itself, and $\log{n}$ (or $\log{N}$) is the number of digits. I find using the same symbol with different capitalization for two different concepts is very misleading and error-prone, but you are of course free to convert to your own notation.
Jan
29
comment How do I derive the time complexity of encryption and decryption based on modular arithmetic?
Note $\log{d} \approx \log{n}$ but $\log{e}$ is independent of $n$ - since $e$ is generally taken as a small value, so in this sense $O(\log{e}) = 1$ (slight abuse of notation). I assume this is the RSA algorithm.
Jan
28
comment Do practical key-less cryptosystems exist?
I think we can assume that IV's and counters will never feasibly repeat for a decent block size (128 or 256 bits), the only problem left being key compromise: how to recover if the key is leaked? do you lose backward and possibly forward secrecy? etc..
Jan
28
comment Do practical key-less cryptosystems exist?
Look up "security by obscurity" and "Kerckhoffs's Principle".
Jan
27
reviewed Reviewed Theoretical pi-based stream cipher
Jan
27
reviewed Reviewed How to generate a key using any m passwords out of total n?
Jan
27
reviewed Reviewed Any implication of a Yale result to security of quantum cryptology?
Jan
27
reviewed Reviewed RSA private key format for Mega
Jan
27
reviewed Reviewed Secure communication between multiple peers on a public channel
Jan
27
comment Secure communication between multiple peers on a public channel
Until we can see how it works, I call snake oil on this. But apparently you're applying for a patent as well, so, never mind.
Jan
27
reviewed Reviewed What is a block cipher?
Jan
27
comment What is a block cipher?
@Oleski Well, that only works if you are guaranteed your message never contains bytes with zeros, if that's not the case your padding will be ambiguous. See this link for more general ways to do it.
Jan
26
comment Cryptographic Symmetric Stream Cipher
If S and P are inverses of each other then you can put any block cipher in their place and all your conditions will be satisfied, with the exception of semantic security which requires the ciphertext to be strictly longer than the plaintext. Though I don't understand the use-case, how would you 'use' this system in real life?
Jan
26
comment Theoretical pi-based stream cipher
@fgrieu The question mentions a one-time-pad, but if we downgrade to stream cipher security, I know not of any such result either. It could work, but we're relying on unproven assumptions here (that it isn't possible to efficiently match an $n$-digit long string in base $b$ with its first occurrence in $\pi$, for all we know an algorithm exists to do it in time faster than $O(b^n)$).
Jan
26
awarded  Yearling
Jan
26
comment Theoretical pi-based stream cipher
Ah, I did not see Joshua's assumption - sorry! That'll teach me to comment without reading the entire thread..