Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [proof-of-work]

This tag should be used for questions regarding how Proof of Work works and Proof of Work algorithms. Proof of Work is a scheme where a 3rd party can verify that someone performed at least a certain amount of work to produce something. This is used in Bitcoin mining.

0
votes
0answers
25 views

Proof of Work to Create a Transaction

I make a little bit of context, so if there's something wrong in my assumptions I'll be corrected. We can say that PoW solves essentially two problems: double spending and decentralization, in the ...
0
votes
0answers
16 views

Byzantine Fault Tolerance Threshold of Bitcoin: 1/2 or 1/3?

According to this answer: https://bitcoin.stackexchange.com/a/58908/41513 a Byzantine Fault Tolerant (BFT) consensus threshold is 1/3, that is contrary to belief that the Bitcoin network is secure (...
0
votes
1answer
27 views

is the proof-of-work for safety or efficiency?

i am reading the proof-of-work (aka: pow, target threshold, difficulty, etc.); my understanding is that pow adds a requirement to validate block headers, so that both benign and malign nodes need a ...
0
votes
0answers
22 views

Decentralised Partial Proof of Work Ideas

In the mining pools, the miners are supposed to submit shares for partial PoW. Put in another way, by solving an appropriately simpler puzzle instead of the puzzle with the true difficulty, they can ...
-2
votes
0answers
30 views

Proof of work failed

I am trying to create a new coin using Bitcoin code base following this https://bitcointalk.org/index.php?topic=3345808.msg35016844#msg35016844 article. But i am stuck as I received an error: 2018-10-...
0
votes
0answers
17 views

What Proof of Work does IOTA use?

I have some trouble finding valid information about IOTA. Actually I would be nice if there would be a good source. So my question is: Bitcoin uses the SHA-256 twice and some "target bits" for ...
1
vote
1answer
44 views

Partial Proof of Work in Pools

Technically speaking a full PoW solution is one whose hash value is below a certain threshold value say V. It is not equivalent to saying that the hash value must begin with say X number of zeros (...
2
votes
1answer
24 views

Is this calculation of mining probability using the Bernoulli trial formula accurate?

I'm trying to understand the formulas for successfully mining a block (without a pool) based on hashrate over time (i.e. to chart the probability of finding a block at various historical points ...
0
votes
1answer
65 views

How to start Proof-of-stake phase after pre-mining the coin in Proof-of-work phase?

I am learning to develop a new cryptocurrency on my own, for the same i decided to develop a Proof-Of-Stake coin, I forked the Okcash for this purpose. And was able to change the coin according to my ...
2
votes
1answer
53 views

Proof of work: average number of tries to create a block

First, I'm sorry if I'm asking a stupid question. I'm just trying to understand bitcoin. I'm reading the Ethereum white paper, and I couldn't understand this sentence about proof of work: At the ...
3
votes
1answer
72 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 ...
0
votes
1answer
47 views

Is “Proof-of-work” a subset of “Byzantine fault tolerance (BFT)”?

Can we say that Proof-of-work is a type of Byzantine fault tolerance (BFT) ? In other words, is PoW a subset of BFT ? Or they are two different categories? Please note that there is a similar ...
0
votes
1answer
18 views

How is the amount of proof-of-work invested in a chain calculated?

The bitcoin whitepaper (page 3) states The majority decision is represented by the longest chain, which has the greatest proof-of-work effort invested in it. I could not find how exactly this ...
0
votes
2answers
56 views

What is the reason to pay miners “monetary rewards” for mining process?

Is it correct to say that: In Bitcoin, it is crucial to incentivize miners by monetary reward, because mining process has significant monetary cost (energy/electricity cost). ? otherwise, mining ...
0
votes
3answers
40 views

What is resource of mining rewards

How the coins must be paid miners for mining process is provided? One of resources may be transactions fee. Is there any other resources for proving reward of miners?
0
votes
1answer
47 views

What is the “main” difference between consensus mechanism of Bitcoin and Ethereum?

Bitcoin and Ethereum both use proof-of-work (PoW) consensus mechanism. One of differences between Bitcoin Pow and Ethereum PoW is difficulty level, meaning that while in bitcoin block generation rate ...
0
votes
0answers
18 views

Why did satoshi choose 10 minutes for duration of each block [duplicate]

Why is a constant 10 minutes used for the generation of each block? In other words, why is the difficulty of generating the proof of work adjusted so that a new block is generated about every 10 ...
0
votes
2answers
36 views

What would happen if PoW cost were drastically reduced or eliminated?

Assuming Bitcoin had a different method for selecting winning nodes and controlling block time creation, please describe step-by-step how the Bitcoin network would be vulnerable to various attacks. ...
2
votes
3answers
210 views

PoW 51% attack vs. BFT 1/3 attack?

So from what I understand, Bitcoin's PoW is prone to 51% attack, but as a distributed system it is also prone to BFT's 1/3 attack right? I think it's mathematically proven that in a distributed system,...
0
votes
0answers
21 views

What is the error rate when mining blocks ?

I am doing the Coursera course on Bitcoin and Crypto tech, and there is a formula defined : Goodput = Throughput * Success Rate. 'Throughput' is defined as how quickly we are finding blocks, whilst '...
0
votes
1answer
27 views

Ethereum's PoW difficulty

Bitcoin's block time is about 10 minutes while that of Ethereum is 15 secs. Both are using PoW at this moment, right? How come Ethereum's block time is so short compared to Bitcoin? Is hashing a lot ...
2
votes
2answers
42 views

Blockchain validation process is linear?

I've read at a few places that the nodes validate transactions in a linear fashion, i.e. after node A validates, then node B, etc. (which is also the reason, as claimed by many, why blockchain suffers ...
1
vote
1answer
27 views

Security via Proof - of - Work

I am reading Satoshi's original paper, merely for the sake of understanding the concept. I have minimal computer science background (some), mostly just mathematics. In Section 4. Proof of Work of ...
1
vote
2answers
58 views

What happens if full nodes don't check for double spends or deliberately lets a double spend TX pass and then this full node relays the transaction?

I am studying about Bitcoin and Blockchain tech via the Princeton crypto course, and it mentions that Full nodes do the following checks : i)transaction is valid with the current blockchain, ii)...
0
votes
0answers
34 views

Why this alternative method to mining will fail?

From what I understand, we need mining to validate the block, we need the proof of work to limit the number of miners can add a block, and we need the block interval to give time to the new block to ...
1
vote
1answer
52 views

Why not to mine more efficient?

I'm a kinda newbie here. But this is what I completely can not understand. If every single miner have to 'arrange' transactions and then compute a SHA-256 function of a given memory chunk, and if ...
1
vote
1answer
40 views

Is it a problem that miners participate in a pools? [duplicate]

I am talking about miners centralization with large pools. Is it a problem? I think there are some possible ways to prevent miners from pooling. For example add miner signature to the block header, ...
1
vote
1answer
40 views

On a low level, how are long chains kept secret and later broadcast during 51% attacks?

I've been reading about the vulnerabilities of PoW crypto, and there's a part of it that I don't understand. Suppose I wanted to stage a 51% attack on Bitcoin (not really feasible, but bear with me). ...
0
votes
2answers
41 views

Proof of Work: email versus bitcoin

I have read "Hashcash is a proof-of-work algorithm that requires a selectable amount of work to compute, but the proof can be verified efficiently. For email uses, a textual encoding of a hashcash ...
0
votes
0answers
10 views

PoW for delay tolerant networks on consumer devices

1) Can the PoW algorithm be rewritten to be more egalitarian and "device-aware"? The system currently has it's weaknesses. One is rapid consolidation... as most mining power today is provided by “...
7
votes
1answer
1k views

What prevents similar time-warp attacks in Bitcoin as happened to Verge?

Right now (may 2018), Verge (an altcoin with proof of work) was attacked by time-warp attack. More can be read here https://blog.theabacus.io/the-verge-hack-explained-7942f63a3017 What exactly ...
0
votes
1answer
63 views

Is the bitcoin blockchain really non-corruptible? [duplicate]

Some people say that proof of work is better than proof of stake, because it's not possible to rewrite the whole blockchain on-spot. One would need to "re-mine" everything. But I think this is not ...
1
vote
1answer
99 views

My coin - Proof-of-Action

I am writing a project on cryptocurrencies. As a part of this project, I thought of a new token for web services exchange. I tried to combine PoW and PoS and here is what I have. I called it Proof-of-...
0
votes
1answer
22 views

What other proof methods are there? [closed]

I am familiar with the proof of work method and a little with the proof of stake method. Is there any more methods that are out there and how do they work?
5
votes
1answer
484 views

How does scrypt pow work?

Bitcoin's pow is sha256, the hash of header is taken and check against a given target to see whether it is smaller than the target, this can be easy seen as block hash starts with zeros. But how does ...
0
votes
1answer
29 views

Validation methods beside POW etc

Are there other concepts for the validation of the next added block to the blockchain beside POW, POS etc.? Of cource there are, but is there a methode that is shining out of the mass? A methode that ...
0
votes
0answers
53 views

how to model stale blocks rate

In this paper "Information Propagation in the Bitcoin Network" the authors measured stale blocks in bitcoin and got a rate of 1.69% stale blocks. This is due to block propogation delay. The authors ...
0
votes
1answer
119 views

Difference between Hashcash proof of work algorithm and Ethash proof of work algorithm?

Understand that each proof of work algorithm has its pros and cons. Difference between Hashcash proof of work algorithm and Ethash proof of work algorithm? Nathan Aw
0
votes
2answers
135 views

Why are blocks in a permissioned blockchain linked together?

My question: Do the blocks in a blockchain without proof-of-work (i.e. a permissioned blockchain) have to be linked together via a cryptographic hash? Longer version of my question: (Please correct ...
0
votes
2answers
312 views

Why miners solve a puzzle in proof of work

I am new to block chain, In PoW, I know a puzzle is given to the miners to solve and the miner who solve the puzzle and find the nonce first will create the block. But I don't understand why there is ...
4
votes
1answer
80 views

How can one blockchain with the same block heigth as another, have more Proof-of-Work

I am reading Andreas M. Antonopoulos's book and In chapter 10 - Assembling and Selecting Chains of Block he writes: Under most circumstances this is also the chain [main chain] with the most block ...
0
votes
1answer
39 views

What are the hashes that miners need to do to create a block? [duplicate]

I’m bit stuck in the concept of mining. What are the hashes that need to be created in each block and the chain? Let’s say that we have block A - B - C forming a chain. One source said that we need ...
1
vote
1answer
62 views

What happens to the blockchain after the miner wins the puzzle?

I have some problems understanding the flow of consensus mechanism, so far I know, In PoW when validating a transaction the miners will compete with each other to solve a puzzle, the miner who find ...
0
votes
0answers
82 views

How often should a mining pool be notifying workers about new work (cancelling current jobs)?

I'm trying to get a handle on the Stratum mining pool protocol. If I set up a mining pool client, I will initially get something to work on. Let's say it takes me a while (e.g. an hour) to solve the ...
0
votes
1answer
67 views

When does a node mark a transaction as confirmed or unconfirmed?

As new transactions are broadcasted, the nodes keep them in a pool of unconfirmed transactions. One node will add it to a block as soon as it finds a proof of work. At the same time many other nodes ...
0
votes
1answer
30 views

The “work” in proof of work

How does proof of work function? Why does the "work" in proof of need to have zero utility for the economics of the cryptocurrency to be viable.
0
votes
0answers
58 views

If a stratum client is submitting completed work, would they need to implement the “mining.submit” protocol?

I wanted to try and better understand how a Stratum client communicates with a pool, so I was experimenting with this NodeJS project -- https://github.com/arnabk/stratum-client/blob/master/README.md . ...
5
votes
5answers
146 views

How to protect the early stages of a proof-of-work application?

For a given cryptocurrency or other blockchain application, proof-of-work provides intrinsic security in the algorithm itself that makes it unlikely that someone can attack the network unless they ...
0
votes
1answer
39 views

How do offchain transactions get validated/confirmed whilst using Lightning network?

How do offchain transactions get validated whilst using Lightning network?
0
votes
1answer
51 views

What was the first transaction which resulted in the very first bitcoin being mined [duplicate]

OK, so I understand that bitcoin in introduced into the system when mining is performed. And mining is a process of adding transactions records to the bitcoin chain of blocks. And transaction (...