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Feb
21
comment Practical usage of S/KEY
You know that S/KEY and OTP have serious problems if they are used on their own (e.g., over an insecure channel, or if the user does not carefully check who they are authenticating to every time), right? That might be why you haven't heard of much deployed use of it.
Feb
21
comment Seed / reseed DRBG too often?
Actually, the premise that you need to reseed periodically ain't necessarily so. Some documents might suggest that reseeding is mandatory, but if you choose a good DBRG, it's not strictly necessary. The decision of whether to reseed should be based upon a thoughtful risk analysis, not just a blind rule-based "the standard says I have to reseed so I guess I have to".
Feb
21
comment Is there a “brainwallet” for GPG keys?
@RobKohr, you might personally think that password quality not a problem.... but in practice, it is a problem. A 5-word passphrase might have entropy as low as 50 bits or lower. That's not enough to resist off-line attack and would have security problems if you faced a serious motivated adversary.
Feb
21
answered Compared to GCM or XTS modes, how secure is H xor R1, E (R2, R1, Message) for confidentiality and integrity?
Feb
18
comment Proving that a function is not a OWF (One-way-function)
@Pinocchio, yes, for a random $x$. Yes, my answer does not depend upon how $f$ is constructed; it applies regardless.
Feb
18
answered Proving that a function is not a OWF (One-way-function)
Feb
18
comment Proof of work for standard computers
Two candidates come to mind. (1) Find an input to scrypt that makes the first 20 bits of its output all zeros. Verification is now pretty cheap. (2) Use timelock puzzles. They admit a very large ratio between the time to solve the puzzle vs the time to construct the puzzle (or to verify the solution).
Feb
16
comment Known vulnerabilities in (EC-)KCDSA
jimmy, Have you done a literature search? That's the obvious first step.
Feb
16
comment ML/NN Cryptanalysis
My advice would be to stick to one question per question. Here you have 3 separate question, all concatenated into the same question box. That isn't a good fit for this site; a good question should have a single answer. (Actually, the 3rd one -- "any other tricks..." -- is also not a good fit, as it is too unfocused.) Also, we expect you to do some research on your own and tell us what you've tried; I don't see that in the question at present. Finally, I suggest starting from the goal (drive in a nail) and ask for a solution, rather than starting with a hammer and looking for nails.
Feb
16
comment Where can I find source code of a compiler that secures a circuit (or attemps to)?
Others have expressed the view that requests for implementations are off-topic on this site. See meta.crypto.stackexchange.com/q/191/351.
Feb
13
answered OTP sequence uniqueness
Feb
12
comment Proof of work for standard computers
Can you please disclose your relationship to Cuckoo Cycle in the answer, to comply with site standards about this? Thank you.
Feb
11
answered How can we sign a contract digitally between two parties?
Feb
9
reviewed Approve suggested edit on RSA assumption and cryptography
Feb
8
answered One-time digital signatures
Feb
8
comment Generating Diffie-Hellman parameters efficiently
Right on, @RickyDemer -- thank you! Fixed.
Feb
8
revised Generating Diffie-Hellman parameters efficiently
added 4 characters in body; added 84 characters in body
Feb
7
answered Generating Diffie-Hellman parameters efficiently
Feb
7
revised Generating Diffie-Hellman parameters efficiently
Improve title, tags, and grammar.
Feb
7
reviewed Approve suggested edit on Generating Diffie-Hellman parameters efficiently