jjj
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Proof of work designed for CPUs?
Accepted answer
11 votes

CryptoNight, the pow function used by Monero is such a function. https://monerodocs.org/proof-of-work/cryptonight/ Basically it needs more random memory accesses, and GPU memory is not designed for ...

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Cracking Elliptic Curve Cryptography
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5 votes

To compute $kG$ you need $O(log(k))$ operations. (For every bit, double the result and and additionally add $G$ if bit is $1$). As you mentioned in a comment for around $k=1024$ you would need like $...

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What is the name of this public key encryption cryptosystem?
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4 votes

Maybe I miss something, but after some quick thoughts about that algorithm, I think it is not secure. Therefore it may not be used and be more like an example for teaching (with no name). The problem ...

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Zero knowledge RSA public key
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3 votes

Yes, it is even possible without interaction (nothing Bob needs to send to Alice). The method is called "ring signature". Let's say she wants to sign a message like "I am Alice an ...

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secp256k1: is it theoretically possible to generate same signature with different key, message hash and k?
3 votes

It is totally possible and fairly easy to see without any advanced maths. The curve has order n (n Points in the curve) the private key d is [0... n-1] and the random number k [1... n-1] and there are ...

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Why is a Feistel Network invertible?
2 votes

You don't need to invert the $f_i$ to invert the whole function. You know $L_d$, so you know $R_{d-1}$ and the the input of $f_d$. The xor can reverse itself. So you get $L_{d-1}$ by simply ...

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Time Complexity of Exhaustive Search Algorithm
1 votes

This is more an answer to why the uniqueness of the sums effects the size so much that the case for $52485332$ becomes trivial (its way to long for a comment). When all sums must be unique, then they ...

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Fully understanding bitcoin transcation verifying and secp256k1
1 votes

G is a point on the curve, but multiplication on elliptic curves is not the same as just multiplying the x and y value by the number. Have a look here https://en.m.wikipedia.org/wiki/...

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How to hack pass-protected private RSA key
0 votes

The encryption of the key has nothing to do with RSA. Cracking it is as hard as cracking every other encrypted stuff using the same encryption algorithm (not RSA, because it would be encrypt ...

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Would hashing a password twice prevent naive attacks?
0 votes

It depends on what "naive" means. In general that is not a good idea. You assume that the attacker does not know that you hash the password twice. If this really is the case, than yes, it ...

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Transparent Voting and Advance Secret Code
0 votes

Blockchain is just a tool to make communication 100% transparent and to avoid a central authority. Yes there are other ways to allow anonymous voting. I know of two ways. A simple approach is that ...

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