All Questions
Tagged with zcash or cryptocurrency
291 questions
2
votes
1
answer
62
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 ...
- 123
4
votes
1
answer
212
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. ...
- 41
2
votes
0
answers
77
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 ...
- 129
1
vote
0
answers
298
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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 ...
- 143
6
votes
3
answers
1k
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 ...
- 163
2
votes
2
answers
641
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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
0
answers
1k
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 ...
- 145
1
vote
1
answer
113
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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" ...
- 11
6
votes
1
answer
3k
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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 ...
- 191
-1
votes
4
answers
810
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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 ...
- 101
1
vote
0
answers
81
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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-...
- 597
2
votes
1
answer
1k
views
Can Blake2 be a replacement for double SHA-256?
Is it a good choice to drop double SHA-256 and use straight Blake2 in a Bitcoin-like blockchain (more POS oriented so it's not a mining problem)?
I'm talking about Blake2 because I've read more about ...
- 123
0
votes
2
answers
1k
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:
...
- 1
0
votes
1
answer
590
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
11
votes
3
answers
6k
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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
2
answers
300
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 ...
- 504
1
vote
0
answers
31
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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\...
- 111
1
vote
2
answers
1k
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 ...
- 357
3
votes
1
answer
493
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-...
- 670
2
votes
1
answer
573
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
1
answer
102
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 ...
- 123
1
vote
0
answers
138
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 ...
- 11
0
votes
1
answer
697
views
How can I prove ownership of hardware wallet? [closed]
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 ...
- 101
1
vote
0
answers
57
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 ...
- 157
0
votes
2
answers
2k
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 ...
- 143
0
votes
0
answers
62
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 ...
- 9
-1
votes
1
answer
135
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 ...
- 99
2
votes
0
answers
970
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 ...
- 21
-1
votes
1
answer
114
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, ...
- 11
-1
votes
2
answers
155
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 ...
- 1,383
0
votes
1
answer
126
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 ...
- 149
1
vote
0
answers
43
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 ...
- 111
2
votes
1
answer
252
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 ...
- 968
2
votes
0
answers
105
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:
...
- 71
1
vote
0
answers
47
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 ...
5
votes
3
answers
18k
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
- 151
1
vote
1
answer
167
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, ...
- 117
3
votes
1
answer
250
views
Creating a private cryptocurrency without trusted setup
I am interested in creating a cryptocurrency that 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-...
- 33
4
votes
3
answers
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 ...
- 65
0
votes
1
answer
875
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. ...
1
vote
1
answer
224
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 ...
- 119
-1
votes
1
answer
210
views
Is it possible to depict the bitcoin mining problem as a TSP-metric problem?
I wonder if someone can represent the blockchain encryption problem (used to mine bitcoins) as a TSP-metric problem (where TSP = Traveling-Salesman Problem). Any approach or intuition of the idea to ...
- 119
1
vote
1
answer
213
views
Is the proof-of-work algorithm "Quark" insecure?
I recently found out about Quark here.
Apparently it is a proof-of-work algorithm used by several cryptocurrencies and is based on a single-level hash function, which consists of 9 different levels of ...
- 153
2
votes
2
answers
238
views
Doesn't d6 to binary for 256-bit bitcoin private key generation produce biased results?
If the mapping table looks like:
1: 000
2: 001
3: 010
4: 011
5: 100
6: 101
Then you are guaranteed that your key will never have a chain of 4 or more 1s, much fewer chains of 3 ones than would ...
- 23
4
votes
3
answers
2k
views
What's the difference between a hash chain, transaction chain and a blockchain?
Can anyone explain to me what the difference is between a hash chain, transaction chain and a blockchain?
- 41
1
vote
2
answers
633
views
Can we retrieve his private key using his public key in ECC?
A paper wallet is the name given to an obsolete and unsafe method of storing bitcoin which was popular between 2011 and 2016. It works by having a single private key and bitcoin address, being printed ...
- 11
2
votes
0
answers
267
views
ZK Proof that a blinded message (for a blind signature) contains a certain value
I am toying with eCash systems and blind signatures, and I started with Chaum's original formulation.
In particular, I'm using this formulation from this link:
User ...
- 236
3
votes
2
answers
408
views
How blockchain system manages it's memory limit for nodes?
As we know, in the blockchain system every node has historical data that contains all previous transactions to maintain the integrity and approve the future transaction. What if blockchain is ...
- 131
1
vote
2
answers
427
views
How does this formula work $(aG + bG) = (a + b) G$ in ECDSA?
Please explain how does this formula $(aG + bG) = (a + b) G$ work in ECDSA?
According to the source:
$a$ and $b$ are different private keys
Suppose
$a = 3$
$b = 4$
then the public key is $Q = aG$...
- 19
1
vote
1
answer
64
views
Cryptography in virtual currencies [closed]
Apart from bitcoins and altcoins, are there any other virtual currencies (like game currencies, gift cards or coupons) that include cryptography in their algorithm?
- 11