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Apr
29
accepted Multiple-prime RSA; how many primes can I use, for a 2048-bit modulus?
Apr
28
answered Pseudocode for constant time modular exponentiation
Apr
28
comment Simplified Key Wrapping to Achieve Only Confidentiality?
Ignoring authenticity/integrity is a really bad idea. It has led to successful attacks on confidentiality in the past. I strongly recommend against this sort of thing; use authenticated encryption or an authenticated key wrap algorithm that does provide integrity + authenticity.
Apr
26
comment Tiger Tree Hash vs generic Merkle Tree
Would you care to edit your question to define TTH? Maybe spell out the acronym, give a link, etc.? Also, I encourage you to describe what research you've already done to try to answer the question on your own.
Apr
26
comment Timestamping using a hashed linked list and public known events
@jliendo, I've edited my answer accordingly. The bottom line remains the same.
Apr
26
revised Timestamping using a hashed linked list and public known events
added 1060 characters in body
Apr
26
comment Zero-knowledge proof of a product
This is an excellent start, but it proves that $xy \equiv z \pmod q$, rather than that $xy=z$. I think if you choose $q$ to be $>2k$ bits long, and combine it with a range proof of the size of $x,y,z$, though, this might work. Thank you!
Apr
26
revised Zero-knowledge proof of a product
added 123 characters in body
Apr
26
comment Multiple-prime RSA; how many primes can I use, for a 2048-bit modulus?
@fgrieu, awesome, thank you for the detailed comments! Would you like to either create your own answer or to edit this answer into a form that addresses these issues? I'm not quite sure how to take into account the first issue you mention (about 1% chance of success), so would need help on that. Thank you again!
Apr
26
revised Multiple-prime RSA; how many primes can I use, for a 2048-bit modulus?
Incorporate comments from fgrieu
Apr
26
comment Can I prove set membership and uniqueness without revealing the element?
P.S. I see: the Wikipedia article on commitment schemes is a bit sucky, and it has led you astray. Wikipedia seems to imply that $C(x)=g^x$ is a commitment scheme, but in fact, that's not a good commitment scheme. The Wikipedia article does go to admit that such a scheme is not hiding, but it fails to connect the dots and realize this means that the scheme wasn't a (secure) commitment scheme after all, and thus does not make a good example of a commitment scheme. So, don't rely upon Wikipedia as your main source of information about commitment schemes.
Apr
26
comment Can I prove set membership and uniqueness without revealing the element?
@DrLecter, yeah, you definitely have a misconception about commitment schemes. $g^a$ is not a secure commitment to $a$. It is not hiding (neither computationally hiding nor information-theoretically hiding). As a result, it is not classified as a secure commitment scheme. A secure commitment scheme must be both binding and hiding. Therefore, what you are talking about is not a DL commitment -- it's not a commitment at all; it's just a broken thing that doesn't work. Of course, when I mention using a commitment scheme, I assume you use a secure commitment scheme, not something broken.
Apr
25
comment Can I prove set membership and uniqueness without revealing the element?
@DrLecter, I think you have a confusion/misconception about DL commitments. I'm not sure what specifically you have in mind when you mention "DL commitments", but any commitment scheme (whether information-theoretically hiding or computationally hiding) will conceal what was committed to -- nothing is leaked. It doesn't matter whether the value being committed to is low entropy or not; secure commitment schemes promise not to leak what was committed, even if the value has low entropy. If it's not hiding, it's not a secure commitment scheme. For instance, $C(x)=g^x$ isn't secure.
Apr
25
revised Can I prove set membership and uniqueness without revealing the element?
Fix bugs with wrap-around modulo q.
Apr
25
revised Timestamping using a hashed linked list and public known events
added 453 characters in body
Apr
25
comment Nonlinearity of the J-K Flip Flop
@WilliamHird, I think you might have a misconception. It sounds like you want to design a secure stream cipher, and your approach is to try to find a function that in isolation has some combinatorial properties. This has two problems: (1) to design a secure stream cipher, you need to look holistically at the entire design; you can't just pick out one component/function used in the stream cipher and say that "since it has properties X,Y,Z, the cipher is secure"; (2) designing secure ciphers is very hard, and you're unlikely to do better than existing state-of-the-art schemes.
Apr
25
answered Multiple-prime RSA; how many primes can I use, for a 2048-bit modulus?
Apr
25
asked Multiple-prime RSA; how many primes can I use, for a 2048-bit modulus?
Apr
25
asked Zero-knowledge proof of a product
Apr
25
answered Can I prove set membership and uniqueness without revealing the element?