Questions tagged [cryptocurrency]

A cryptocurrency is a digital currency powered by cryptography. This tag is applicable only to Q&As about the cryptographic mechanisms used by a currency, not for questions about economy, usage, or acquisition of any particular currency. Please note that Stackexchange has dedicated websites for Bitcoin, Ethereum, Monero, etc.

Filter by
Sorted by
Tagged with
2
votes
1answer
47 views

Does applying a “PushEntropy”-function increase security of a private key?

I was just reviewing the source-code of the NBitcoin-package. As far as i can see when you create a new bitcoin-keypair Key privateKey = new Key(); (without passing ...
3
votes
0answers
35 views

Can you elaborate on pBFT for dBFT in relation to PoW and PoS consensus algorithms in layman's terms?

I've read all other related answers and googled this extensively. My intention and background in asking this question is that I am delving into cryptocurrency and blockchain technology in general. ...
0
votes
0answers
44 views

EOS stuck in Simpleos Wallet: billed CPU time (343 us) is greater than the maximum billable CPU time for the transaction (1 us) [closed]

So I got this error message while trying to withdraw my EOS coins to another wallet: billed CPU time (343 us) is greater than the maximum billable CPU time for the transaction (1 us) Then I searched ...
1
vote
0answers
13 views

Are Bitcoin's blocks signed by the miner? [migrated]

To my understanding, at no point in the Bitcoin Whitepaper does it say that blocks are signed by the miner. However, one could see the advantage of having blocks signed. Thus I wonder if in the ...
2
votes
0answers
53 views

How to associate a post-quantum public key with a pre-quantum one in blockchains?

As a layperson, I'm curious if a cryptocurrency could fork to a quantum-resistant algorithm without people losing access to their wallets. Is it possible to generate a quantum-resistant public key ...
0
votes
0answers
93 views

Why wouldn't you just refer to the hash of the jpg file in the NFT storage?

This question is in reference to this tweet. It seems people are using the url of third party websites to record the reference to the content for NFTs. Why can't people just hash the jpg files for ...
-1
votes
0answers
19 views

Directly testing for node honesty

I was thinking... the entire problem with cryptocurrencies is how to prove that honest nodes are honest. I.e. what signal they can send that dishonest nodes can't fake. Bitcoin famously solved this by ...
3
votes
1answer
228 views

How are objects sold as NFT's (“non-fungible tokens”)?

I'm familiar with "blockchain" and the theory and technology behind cryptocurrencies, tokens, and the economics behind why such things are capable of having monetary value, however I've ...
1
vote
0answers
74 views

How Secure Is Splitting A Bitcoin Private Key?

NOTE: This question cannot be posted to Bitcoin SE because it will not render there due to the mathematical notation. Since the mathematical notation is part of the question, this is the more ...
0
votes
0answers
102 views

Bitcoin Key Recovery Without Nonce Re-Use

There are a lot of questions in these forums regarding the recovery of private keys. But I'm here to postulate on something unique to a specific piece of research that I looked into recently. The ...
1
vote
1answer
45 views

Attestation of private key deletion

I recently came across an article outlining a framework for a hypothetical cryptocurrency, the article is here if you care to read the whole thing. The relevant section is the "Digital Cash" ...
2
votes
1answer
303 views

How are new coins minted in Proof of Stake systems

I've been trying to understand Proof Of Stake cryptocurrency systems, but I don't see how new coins are made using the Proof Of Stake system. My current understanding of Proof Of Stake People put up ...
0
votes
4answers
133 views

Would It Be Technically Possible To Delete Old Blocks From A Blockchain Cryptocurrency?

From what I understand, a cryptocurrency mine needs to store a copy of the entire blockchain in order to be able verify transactions, which is why most wallet owners are not miners. The more ...
0
votes
0answers
34 views

Is there any application for ZKP that prove that “I know the pre-image of Hash function”

I'm looking for any applications that using ZKP to prove that "I know the pre-image for Hash function". As far as I know, POUR operation in Zcash uses this concept but I can't find any ...
0
votes
0answers
17 views

On sub-linear ring signatures and transaction sizes

I've been reading Noether's paper on Triptych and its extension Arcturus, alongside a few others exploring sub-linear ring signature schemes. I only have one question. Each paper (RingCT3.0 and its ...
1
vote
0answers
39 views

Hash as encryption used by Monero

Monero uses a Pedersen commitment $yG + bH$ to obfuscate the value of a transaction, where $b$ is the value and $y$ is the blinding factor. For the receiver to know both variables, it uses a Diffie-...
0
votes
0answers
20 views

Cryptocurrencies: Undetectable Nothing-at-Stake - why does it matter?

The paper Formal Barriers to Longest-Chain Proof-of-Stake Protocols (Brown-Cohen, Narayanan, Psomas, Weinberg, 2018) describes an attack on Proof-of-Stake cryptocurrencies called Undetectable Nothing-...
1
vote
1answer
69 views

Can Blake2 be a replacement for double SHA-256?

My previous question was closed because it was too open-ended, so let me simplify the question: Is it a good choice to drop double SHA-256 and use straight Blake2 in a Bitcoin-like blockchain (more ...
0
votes
2answers
36 views

How can I get issuerNameHash and issuerKeyHash from PEM or DER certificates?

I need to get these values ​​from pem and der files. Is there Python and C code or openssl command for these results? Example cert in PEM format: ...
0
votes
1answer
93 views

Calculating the point on the curve during ECDSA signature verification

I'm confused as to how he got (62, 44) as an answer within this article: https://www.coindesk.com/math-behind-bitcoin
8
votes
3answers
543 views

Is double SHA-256 the best choice for Bitcoin?

So I was just curious. I really look up to Blockchain technology and I have read that Bitcoin uses double SHA-256 for hashing. ( from what I understood, double sha256 is essentially $\operatorname{SHA-...
1
vote
2answers
71 views

Clarification questions about timestamp servers

I am reading the bitcoin white paper, and I came across the concept of timestamp servers in it. Unfortunately the description of the usage of a timestamp server leaves me with more questions. And ...
1
vote
0answers
24 views

Map many crytocurrency token IDs (2^512) into a single set of tokens IDs (2^256)

Let we have a finite (small compared to 2256) set $T$ of 257-bit numbers. Need a function $f: T \to 2^{256}$ such that it's almost of zero probability that $f(n)=f(m)$ for two different numbers $n,m\...
1
vote
2answers
226 views

Recovery Passphrase Collission for BIP-39 and BIP-44

Referring to the standards of [BIP-39] and [BIP-44]: a 'master password' consisting of 12 words uniformly selected from a 2048-word dictionary corresponds to 128 bits of entropy, that is then used as ...
0
votes
0answers
25 views

R, S, and Z values in a transaction using the Transaction ID

How can i get the R, S, and Z values and the Public Key using a transaction IDE i have? I knew of a website called 2coin.org which provided these values but now the website is no more active and it ...
0
votes
0answers
19 views

Universal Computation “measurement” using SNARKs?

If SNARKs are able to prove computations of arbitrary complexity and difficulty were executed correctly, would it be possible to use them to create a Proof of Work consensus system where ANY ...
3
votes
1answer
326 views

Can we use Bitcoin miner to break 2Key 3DES, if yes how long it takes?

As ASICs are specifically designed to generate the hash for a block of a block chain. which is much faster than other GPUs which are used to break 2key-3DES. can we use Array of ASICs to break 2key-...
2
votes
1answer
102 views

Cryptographic limit to total accounts in secp256k1

Factoring in birth day attacks and all that, with 256-bit elliptic curve cryptography, lets take secp256k1 as example that Bitcoin uses, what is the maximum number of accounts that are secure? It isn'...
2
votes
1answer
60 views

Why shouldn't cryptocurrency hash algorythms, resist side channel attack?

2015's Argon2 publication suggests that cryptocurrency hashing like password hashing on backend servers should not be subject to side-channel attack: Argon2d is optimized for settings where the ...
0
votes
0answers
28 views

Probability of finding a valid block when cryptocurrency mining

Today I learned that for BTC, the probability of a hash being valid is approximately 1/(D*2^32), whereas D denotes to the difficulty. I was wondering if this is ...
0
votes
1answer
72 views

How can I prove ownership of hardware wallet?

I’m applying for a mortgage loan and I recently made a large deposit into my bank account from crypto stored on a ledger hardware wallet . I sent the funds to Coinbase where I converted to usd and ...
1
vote
0answers
51 views

Cryptography that lets you conceal a secret, but also alerts others of the exposure of the concealed secret?

Is there such a cryptography where I can prove that someone decrypted an encrypted string? Say I wanted to attach a Bitcoin private key in some type of digital container, but in order to open this ...
0
votes
2answers
424 views

Is RSA secure enough to protect bitcoin private keys? [duplicate]

Suppose my very trusting friend has a bitcoin private key with a large balance (let's say $1B USD worth of Bitcoin) and wishes to keep a backup copy with me as a trustee. He doesn't want to transfer ...
0
votes
0answers
35 views

Suggestion on dynamically changing hash algorithms for blockchain

First of all excuse me for my inexperience on the topic (I am new to cryptography). I am currently studying for my Master thesis and am am looking for hash function on which I can modify them so thy ...
0
votes
0answers
44 views

Bitcoin ECDSA signature

I am trying to use the ecdsaSign function in ecdsa.c of https://github.com/kvhnuke/Ethereum-Arduino/tree/master/Ethereum-Arduino/libs which is based on the files in the repo https://github.com/...
-1
votes
1answer
99 views

Why can't miners accept lower fees [closed]

From what I understand about crypto such as Ethereum or Bitcoin, Miners are verifying transactions and being awarded for doing so. Right now Ethereum has some really high gas prices. (Price of ...
0
votes
0answers
212 views

How do you verify that an address is related to a private key

This is my first post. My interest for cryptography is exclusively motivated by cryptocurrencies. My question is: If I generate some keys, how do I actually verify that the address is indeed ...
-1
votes
1answer
88 views

Destroy bitcoin-qt curve parameters real or not? [closed]

Good night everybody. Is it real destroy all EC parameters in bitcoin client ? If remove "+7" and replace base point to (0,0 or 1,1)in algorithm then making a new address or public key, ...
-1
votes
1answer
61 views

Is it safe to store mnemonic seed in the email if I change random 2 words?

If I store 12 word seed in the email like gmail and my phone as well but change 3rd and 7th words in the seed for example with other bip-39 words and remember it, would that be safe? I can't think of ...
0
votes
1answer
115 views

To what extent would Bitcoin be private without address reuse?

Let's say Bitcoin had these rules from the start: An address with balance cannot more receive money An address must use all its money in one transaction This would prevent address re-use. To what ...
1
vote
0answers
24 views

What guarantees that a mined block will be accepted on the network? (Blockchain)

What ensures that a mined block will be accepted on the network? I mean, if I mine a valid block in the blockchain, and I transmit it to the network, what is the incentive to people accept it? Doesn't ...
2
votes
1answer
92 views

What is the maths behind Bitcoin's BIP32?

I've read about BIP32 key derivation functions. I'm trying to understand how, given a secp256k1 key pair, that "child" public keys may be generated from just the public key, and the ...
2
votes
0answers
78 views

How hard is it to link a hardened BIP32 child public key to it's parent public key?

The BIP32 spec says this in the security section: ...
1
vote
0answers
23 views

Size of messages in timing attack on RSA Montgomery

I'm codin' timing attack on RSA Montgomery which compares two sets ( the first one includes those which need a reduction in contrary to the second one ). But I got troubles with the Montgomery ...
1
vote
3answers
1k views

How can i check if a public key match with a private key

Is there a way to check, (with openssl command for example), if a given public key match with a private key ? Thanks
1
vote
1answer
71 views

Could multicollisions be used to mine large amounts of cryptocurrency?

I'm reading about hash functions at the moment, and in the book I'm reading there's a section on multicollisions. Specifically, using a 2-collision to find $2^N$ collisions in $N2^N$ time. If, ...
2
votes
1answer
108 views

Creating a private cryptocurrency without trusted setup

I am interested in creating a cryptocurrency which keeps the sender, the receiver and the amount private and does not require a trusted setup. I have already read the Zerocash protocol but It uses zk-...
4
votes
3answers
1k views

Why do people criticize and mistrust the e-voting based block chain?

I am planning to implement an e-voting system based on hyperledger fabric blockchain, however, I came across many criticisms from well-known security experts like Josh Benaloh and others. The problem ...
0
votes
0answers
195 views

Comparisons of ECDSA, EdDSA and BLS Signatures in Blockchain: Pros and Cons

As we know, the most used digital scheme in Blockchain is ECDSA. For now, more and more blockchain projects, I've noticed, are considering substituting EdDSA and BLS signature scheme as the new one. ...
0
votes
1answer
97 views

Why mining bitcoins is difficult?

As I understand to obtain a Golden Block is to finding a nonce that matches a hash lower than a given target, as shown in this research-gate article. And here is a "py" kernel: Bitcoin mining python (...