Questions tagged [algorithms]
Regarding the underlying algorithms related to Bitcoin protocol.
106
questions
10
votes
3
answers
3k
views
How can I manually (on paper) calculate a Bitcoin public key from a private key?
I am interested in generating a Bitcoin address by hand for security's sake. After I choose/generate a private key, how do I generate the public key?
From there, how would I double check my work?
...
5
votes
1
answer
156
views
Why does bitcoin.core's algorithm uses ancestor score instead of just ancestor fee rate to select transactions?
In bitcoin.core's implementation of the greedy knapsack algorithm to select transactions to go into a block for mining, the heuristic used to order transactions is based on an "ancestor score&...
1
vote
2
answers
39
views
Where is a good source of information for procedural algorithm to program my own Bitcoin QR code generator?
Not trusting those already available QR code generators available, I would want to program my own. The idea is to input a Bitcoin key ( private or public ) and the program would simply generate the ...
2
votes
1
answer
237
views
SegWit signing algorithm and its improvement
I was reading about Segregated Witness upgrade from the book Mastering Bitcoin by Andreas and there were some questions I have not figured out. I am appreciated to get some of your help!
A) There was ...
0
votes
2
answers
67
views
If there was an easy way to check for double spends, will consensus algorithms be needed?
Currently, checking for double spends is very computationally expensive, so consensus algorithms, like POW, were put in place to more easily prevent double spends among other things.
Ignoring the fact ...
0
votes
0
answers
25
views
What exactly determines how long it takes a given miner to mine 1 btc block? (not talking about hashrate) [duplicate]
So given the number of miners out there working on doing the same thing and that 1 block is mined every 10 minutes, it would appear at face value that only those with the highest hashrates would ever ...
0
votes
1
answer
69
views
Why is SHA-256 mining secure?
My understanding is the when you are mining bitcoin you are looking for a string, or maybe a binary number (a) such that if you 'add' a to the block (b) you get a number (c) whose hash begins with a ...
4
votes
1
answer
766
views
In Bitcoin, what happens if there is no viable nonce?
I'm assuming SHA is perfectly uniform.
In bitcoin, there are $2^{32}$ possible inputs per block, which are mapped to $2^{256}$ possible outputs. So there is a $1/2^{224}$ chance that any randomly ...
2
votes
1
answer
78
views
Why do we need 2F prepare certificates instead of just F+1 in PBFT?
I started reading PBFT and I could not understand: why do we need 2F prepare certificates?
The client needs only F + 1 replies, not 2F, so why can't the same rule be applicable in the prepare phase of ...
1
vote
2
answers
317
views
What is the optimal way to increment extranonce?
I'm trying to learn how to block headers are created and an efficient way of doing so. Given a list .of transactions, can I change the extranonce without having to rehash the entire list?
EDIT: To ...
2
votes
2
answers
483
views
Is verification of a blockchain computationally cheaper than recreating it?
One of the advantages of cryptocurrencies like Bitcoin that is often repeated is how hard it should be to manipulate past transactions. The reason that is often stated is that you would have to re-...
6
votes
1
answer
410
views
What are the differences between Bitcoin and Libra?
Recently, Facebook announced to launch a crypto currency called "Libra". Libra is managed by associations under the name "Libra Association", see https://libra.org/en-US/association/.
What are the ...
3
votes
1
answer
2k
views
What is the difference between BFT and PBFT
What are the differences between BFT and PBFT?
I want to know the difference between these two concepts.
If there is any improvement in the BFT's limitations, let me know.
Please answer. Thank you.
0
votes
0
answers
10
views
what happens when their is a bicoin algorithm half? [duplicate]
I saw in an article something about a bitcoin algorithm half in 2020, what exactly is this, I have tried looking this up but I couldn't find anything that told me what it was only this.
3
votes
1
answer
140
views
Why haven't a large number of cryptocurrencies copied Primecoin's mining algorithm? [closed]
According to my understanding, generating an ever-growing list of prime numbers benefits mathematics and society in some mysterious way. Given this, why have more recently created proof-of-work ...
1
vote
1
answer
601
views
What happens if I use same k twice in DSA algorithm?
To sign a message , we choose nonce k but what happens if we use same k twice to sign a message using DSA algorithm?
3
votes
1
answer
970
views
Could Bitcoin be based on accounts instead, more like banks?
In banking, a user's account will have a balance, and when they spend an amount is credited from their balance. For example, the account #310 could have $100, and spending $10 would reduce it to $90.
...
0
votes
2
answers
84
views
I want to know how I can express a phenomenon found in Merkle Trees mathematically
I want to know how I can express a phenomenon found in Merkle Trees mathematically. If I want to figure out which leaf node in a Merkle Tree has changed I can look at the authentication path to figure ...
2
votes
2
answers
268
views
Crypto exchanges algorithms
I have noticed that if I put a buy order up - for instance - on any not so heavily traded coin, if close to the highest bid, often within 20 secs the highest bid will try to beat me.
Or when I put it ...
0
votes
1
answer
217
views
How can I check what mining algorithm does an altcoin use?
Where in the sourcecode files can this be checked?
For example, lets get a specific coin:
Chronon
https://github.com/ChrononGroup/Chronon
In what file can one check the mining algorithm?
0
votes
1
answer
113
views
How many transactions per second can blake2s algorithm can handle?
i saw the hash functions speed (miBps) are 947 according to this website: https://blake2.net/
but how many transactions blake2s algorithm can handle? Verge uses the same algorithm right?
more about ...
0
votes
1
answer
117
views
Is the whole idea of proof of work or proof of stake quite unnecessary and superfluous for cyptocurrencies?
I only have a vague idea of proof of stake, but I think I reasonably understand proof of work. In the case of bitcoin, the whole hash thing business has to be combined with a mechanism to increase the ...
1
vote
2
answers
303
views
How to return tx to mempool from stale block?
This question is centered around the implementation of how transactions from a reorganized block return to the mempool.
In my understanding, once a block becomes organized out of the best chain all ...
0
votes
1
answer
2k
views
Why do I keep getting a connection lost error in Nicehash Bitcoin mining
The algorithm I'm using is daggerhashimoto. At first I thought this was because of my country blocking Bitcoin mining or something, but it doesn't work even if I'm using a VPN (vpnbook.com/freevpn). ...
-3
votes
2
answers
64
views
Any attack vector for Proof of Witness?
When Alice wants to send Bob some coins all she has to do is sign a transfer of ownership with her private keys and publicize that announcement until Bob is happy with the number of witnesses. For ...
1
vote
1
answer
512
views
How is Ethash a 'memory hard' algorithm if it utilizes peak GPU memory bandwidth?
According to the Ethash algorithm described here, the computation for each nonce requires a loop of 64 iterations, where each iteration reads a chunk of 128 bytes from a pseudo-random location in ...
0
votes
1
answer
296
views
Can the Antminer S3 mine Bitcoin using Blake2s algorithm?
If so, how? Nicehash can also do this, so what I'm trying to do is point my Antminer S3 to Nicehash's Blake2s stratum. But will changing the stratum URL be enough? Do I have to set up Blake2s first?
0
votes
1
answer
726
views
Difference between scrypt and sha-256 mining?
So in detail my question is:
are both these two algorithms different from each other?.
I read somewhere that this two algorithm is used for the different cryptocurrency. if that's true. then why?
...
0
votes
1
answer
174
views
which cryptocurrency using Slasher algorithm for Proof of Stake mining process?
Ethash algorithm for PoW mining process on my own cryptocurrency. I need to use Slasher algorithm instead of Ethash algorithm for Proof of Stake process.
My question is Which cryptocurrency using ...
3
votes
1
answer
960
views
Implementing NiPoPoW algorithm
Hello,
We, a small team, have implemented about 95% of a breakthrough scientific proposal that is describing the NiPoPoW Non-Interactive Proofs of Proof-of-Work. You can find our source code ...
0
votes
1
answer
647
views
How an order fulfillment works
I'm trying to understand how order fulfillment algorithm works from technical point of view.
Let's say I created an order to sell 0.8 BTC and buy 5400 XRP along with other orders to sell 0.35 BTC, 2....
3
votes
1
answer
148
views
Understanding what is being run through Sha256
When I am running through an example for Sha256 I am not understanding how to arrive at the right answer. If I use the following Hex string:
...
3
votes
1
answer
359
views
What algorithm do bitcoin miners use to choose which tx to include in their block?
I understand it's in the miner's best interest to receive as many fees as possible for his hopefully-accepted block, hence it should include the most rewarding (fee / size) txs - up to the 1MB limit.
...
6
votes
1
answer
496
views
Does full node store all valid forks and "alternative" blocks from blockchain history?
Forks are possible when mining the blockchain and happen "all the time" during mining.
This means the nodes monitoring the blockchain have recorded many forks during blockchain's lifetime, with some ...
0
votes
2
answers
302
views
At which point and how does the miner who successfully solved hash get coins? [duplicate]
When miner creates a valid block he broadcasts that to the network.
It can happen that someone else did the same. So we have half nodes think that chain+A is correct, and other half that it is chain+...
1
vote
1
answer
264
views
Why are transactions grouped into blocks? (how are new blocks-to-solve formed)
Why are transactions grouped into blocks when put onto blockchain (PART 1)?
Lets say we have just put a block on a chain and there are no blocks at the moment that users mine. At that moment how many ...
0
votes
1
answer
247
views
How bitcoin protocol checks transaction is valid (in particular that inputs are unspent)?
I'm learning bitcoin protocol theory.
To pay to someone you use a transaction. In the transaction you specify some of old transactions that gave you money (so called inputs). These inputs should have ...
0
votes
1
answer
119
views
Does the 100+ GB blockchain database contain every transaction?
Does the 100+ GB blockchain database contain every transaction since the beginning, or only a digest of them?
I've read Nakamoto's paper and I see:
the spent transactions before it can be ...
0
votes
1
answer
3k
views
Nicehash autoselected algorithm with very high difficulty
I'm new at this so please bare with me
I have a couple gtx 750 lying around so I decided to give mining a try.
I used nicehash, according to the site "NiceHash Miner autoselects the most profitable ...
2
votes
1
answer
1k
views
if a Bitcoin mining nounce is just 32 bits long how come is it increasingly difficult to find the winning hash? [duplicate]
I'm learning about mining and the first thing that surprised me is that the nounce part of the algorithm which is supposed to be randomly looped until you get a number smaller than the target hash .. ...
1
vote
0
answers
91
views
Why do different currencies use different units of difficulty? [closed]
I'm trying to understand the relationship between difficulty and network hash rate. I feel like I understand it for Etherium, where the difficulty is the same as the total number of hashes the network ...
1
vote
1
answer
499
views
How do miners decode the input transaction?
When a transaction is broadcasted to the network, the transaction string contains the little-endian of SHA256(SHA256(X)) where X is the transaction string of input transaction.
Now, since SHA is ...
3
votes
0
answers
424
views
Probability of Orphaned Blocks
This is a question regarding the probability of orphaned blocks depending on the block interval. I am using Bitcoin vs Litecoin as an example.
Assuming equal hash rate and number of transactions, ...
2
votes
1
answer
658
views
How do Bitcoin and Litecoin compare in scalability?
Bitcoin and Litecoin are very similar, however they differ in the hash algorithm, the block interval and reward schedule. How do these characteristics impact the scalability in terms of e.g. ...
1
vote
0
answers
2k
views
What is the difference between X11 and X11 Ghost (Gost) [closed]
I'm looking at SIBCOIN. Its algo is X11 Gost. I've been trying to see what differentiates that algo from "plain, vanilla" X11.
2
votes
1
answer
159
views
Mining and pending events
I am trying to fully understand the block chain algorithm and in particular, the consensus.
My understanding is each miner has a pool of pending events -- events that have not yet been included in a ...
20
votes
5
answers
45k
views
How to build a bitcoin trading bot
I'd like to experiment with bitcoin technology, crypto currency, and encryption. I thought the best way to accomplish that is building my very own bitcoin trading bot.
It seems like a daunting task, ...
1
vote
1
answer
715
views
Bitcoin mining algorithm - target - Java
Default share difficulty is 1 (big-endian target for difficulty 1 is 0x00000000ffff0000000000000000000000000000000000000000000000000000)
How to calculate this?
How it look like on Java code?
What ...
4
votes
1
answer
1k
views
Transaction signature algorithm
As I know, standard ECDSA digital signature algorithm returns two values (according to this article or Wikipedia), but transaction push services or APIs, like this one, require one string as a ...
0
votes
2
answers
959
views
Own bitcoin pool miner algorithm
I receive these variables from the mining pool:
job_id, prevhash, coinb1, coinb2, merkle_branch version, nbits, ntime, clean_jobs.
What must I do with them?
Can you write step by step formulas how ...