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.

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112 views

Are transactions verified before miner solves the block?

In the PoW mining equation... Hash = (Nonce x prev_hash x list of transactions) the miners find the nonce to add the block to the blockchain and receive the block reward. As we can see, the hash is ...
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979 views

Is it possible to make PoW ASIC-resistant through dynamically generated hash chains?

Bitcoin's static proof-of-work function SHA256(SHA256(data)) was apparently easy enough to be implement as ASIC which lead to the re-centralization we see today. But what if the PoW function changes ...
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2answers
159 views

How to secure new public proof of work blockchain?

I am fairly new to the bitcoin and blockchain technology and have recently started reading about it. So my understanding and the question bellow may not be very accurate. As I have understood so far, ...
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1answer
3k views

How much “Proof of work accepted by server” needed to generate 1 bitcoin (or a part of it) [duplicate]

I am using Bitminter client, and I am confusing about how much I earn in one week while my system working overnight. https://bitminter.com/ says "Mining one bitcoin with just a PC now takes millions ...
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1answer
176 views

How the first succesful miner is ensured his reward

With my still rather limited knowledge of bitcoin, I was wondering how the correct origin of proof of work is ensured. Specifically, when a miner successful computes a valid hash and is to broadcast ...
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Why can't Bitcoin switch over to Gridcoin's proof of work system?

Gridcoin advertises itself as a "a mandatory competitive reward mechanism based on contributing the most towards BOINC projects on top of existing cryptocurrency technology." Is there a reason why ...
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1answer
118 views

Are the mining incentives of bitcoin compatible with the existence of a competing Proof-of-Work chain? [closed]

Scenario A: A chain split occurs due to a bug or contentious rule change (i.e. the miner incentives aren't changed in any way). Both coins initially start out with the same difficulty (and won't ...
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1answer
9k views

What happens when there are no Bitcoins miners anymore [duplicate]

So if I'm not wrong, the proof of work is the way to validate all the transactions in a Block. The miner gets (at the moment) 12,5 Bitcoins as a reward for each validated block. So my question is: ...
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1answer
486 views

why verification of transaction after proof of work?

I have question about bitcoin protocol. In Satoshi's paper it is mentioned that: New transactions are broadcast to all nodes. Each node collects new transactions into a block. Each node works on ...
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0answers
351 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, ...
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2answers
821 views

How does Peercoin (or other PoS) prevent timestamp forging effecting hash attempts or random minting?

I understand that every second the timestamp & potential transactions is hashed. I guess there exists a "start time" on the block chain we can't roll the clock before because transactions with ...
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What's a good repo to fork if you want to create a blockchain like a “Math” coin or Curecoin. (mining equations, not hashes)

I want to create my own crypto currency and I want to know what's the best github repo to fork when it comes to making a blockchain that's based off of getting the miners to do mathematical ...
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0answers
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Zero-knowledge/Arthur-Merlin Proof-of-Work for NP-like problems with coin flips hashes of recent transactions [closed]

On a previous answer to a question about making proof-of-work more useful, two challenges were provided: "1. The work must be much, much easier to verify than to do, and 2. The work must in fact ...
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2answers
138 views

Would an optimization proof-of-work problem where the entity with the lowest hash wins have any security weakness or other disadvantage?

I am wondering if there would be any security deficiencies if cryptocurrencies such as Bitcoin were to change their proof-of-work problems to optimization contests. For example, suppose Bitcoin were ...
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2k views

How proof-of-work detects Sybil attack in Bitcoin?

I read in several paper that PoW deters Sybil attack in Bitcoin. However, there is no enough explanation about how proof-of-work detects Sybil attack in Bitcoin?
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Limit of Proof of Work [duplicate]

I do not have a complete understanding of bitcoin, but I feel that the PoW concept will not do it in the long run, so I need you to explain to me if I'm wrong. First of all, all this work force is ...
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0answers
112 views

What are bitcoin miners actually solving? [duplicate]

I've read all other answer, but nobody really gives an answer. Whom for are they solving, and what entity outside BTC community has benefits from all the electric energy wasted in the process of doing ...
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118 views

How are miners prevented from doing too much work?

I understand that scripts can be written within transactions that make the miners do some work. How does Bitcoin ensure that scripts that make miners do too much work are prevented?
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2answers
1k views

How can we be sure that a new block will be found?

How do we know the HASH function will produce an output that fulfills the difficulty, i.e. is below 0000...xxxx...xxx? Is it possible that no proof will be found so that the HASH will produce that ...
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1answer
69 views

Proof of work: optimal number of transactions?

I've been struggling with this Q for a while: My initial understanding was that miners start to work on PoW for new block immediately after the previous round's block is confirmed. My Q is this: ...
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3answers
5k views

Are there alternatives for proof of work?

Bitcoin uses proof of work to secure the network, Ripple uses a global consensus system and PPCoin uses proof of stake. Are there any known alternatives to the above methods?
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1answer
212 views

Does 4 byte Nonce enough to proof of work?

Is it always possible to find an hash value of a block, smaller than the current difficulty, just using 4 byte (Nonce) ? How can we be sure about it ?
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1answer
295 views

The 51% assumption

I am new to understanding how bitcoin works but reading up a little on PoS and PoW, I understand that anyone with over 50% of the network resources (bitcoins or computing power respectively) can ...
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1answer
351 views

What is the difference between PoW and PoS regarding computations when determining a new block?

According to Buterin there are 600 trillion computations done per second using SHA256. He and other sources say that PoS solves the issue of not requiring so many computations but I do not completely ...
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1answer
169 views

Zero-BTC transaction fees, service-specific mining pools and external compensation

Bitcoin is a network that is proven to be stable, but if you want applications on top of Blockchains you have to play by the rules of the system. For notary use cases (for example), where you would ...
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1answer
71 views

separating proof of work from mining possible?

I (think to) understand that proof-of-work is the process through which transactions are verified and the health of the network is being ensured. I also (think to) understand miners get bitcoins for ...
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2answers
3k views

What is Proof of Burn?

Can someone explain me: What is Proof of Burn What is the difference between Proof of Burn and Proof of Work How Proof of burn works Which virtual currency uses Proof of burn technology instead of ...
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1answer
2k views

How does a time warp attack work?

I more or less understand how an attacker (with less than 50%+1 of the hashing power) can artificially lower the block difficulty by messing with timestamps. I also understand how such an attacker ...
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1answer
850 views

What prevents a miner from faking nonce hash

What exactly prevents a miner from presenting a random nonce hash of the block with enough zeroes at the start to get chosen? How is the new hash verified by the other nodes? Since as I understand ...
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1answer
638 views

Bitcoin Mining Computational Power [duplicate]

1/ I do not understand why bitcoin mining is random when hashing is deterministic. reference : https://en.bitcoin.it/wiki/Nonce Can the mining pool with the most mining power always win? What value ...
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4answers
7k views

If SHA256 produces an alphanumeric hash, how can a hash be “less than a certain value”?

I was under the impression that Bitcoin's method for validating a hash involved making sure the hash started with a pre-determined number of zeroes. However, after reading the docs here, I see the ...
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1answer
193 views

Why was the chain with the largest work chosen as the metric of consensus?

There seems to be a myriad of ways to find consensus (PoW, PoS, PoD, PoE and various other methods and hybrid approaches). What was the reasoning behind bitcoin being PoW and treating the chain with ...
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358 views

How cooperative or competitive is the mining process?

As each miner works out which nonces it has tried, does it notify the network so that energy isn't wasted on re-processing the same thing by each node? Or is it totally competitive with everyone for ...
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1answer
323 views

Question solved by bitcoin miners [duplicate]

What computational questions are solved by bitcoin miners and what is the computational complexity of one instance of this question. Essentially, how would someone program an application for bitcoin ...
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1answer
840 views

Why was finding a hash beginning with a certain number of zeroes chosen as the proof of work?

It seems to me that the reason the proof-of-work involves finding a hash beginning with a (temporarily) fixed number of zeroes is because one can easily check whether they have solved the problem by ...
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1answer
69 views

Proof of work - does the equipment matter?

It technically doesn’t matter whether I am using a super computer or a laptop to do the proof of work, it’s simply that with a super computer I can go through the attempts much faster, which means I ...
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1answer
468 views

ASIC resistant PoW mechanism that generates new hash functions. How does that work?

From Vitalik Buterin's post regarding "On Mining", he mentions: The second approach is somewhat different: create a mechanism for generating new hash functions, and make the space of functions ...
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2answers
4k views

Probablity Distribution of mining

What is the probability distribution of solving a block, given the same difficulty. So if I try to mine multiple times using the same difficulty, is it normal distribution with mean of 10 minutes? ...
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2answers
4k views

What is the difference in hashing algorithm between bitcoin and litecoin?

I am having trouble finding litecoin mining specifications. I would first of all require something like this: https://en.bitcoin.it/wiki/Block_hashing_algorithm Except for litecoins. I need to know ...
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2answers
1k views

Intrinsically useful proof-of-work using Mersenne or Fermat numbers factorization. Could it be possible? [closed]

I was reading this question and got myself thinking - why can't a crypto-currency use as proof-of-work a difficult problem that has value outside of the network? I understand the effort to produce all ...
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2answers
766 views

What is the most lightweight proof-of-work algorithm?

I know litecoin was created back in the day using Scrypt as to make it more lightweight but also harder to build ASIC hardware from - so everyday computers could mine. Are there other algorithms one ...
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1answer
207 views

Has anyone verified what your CPU is being used to do when it “mines” for bitcoins? [duplicate]

I understand that "mining" for bitcoins requires your computer to do work that you don't monitor, so my question is, how do you know what it is that your computer is doing? Has anyone verified what ...
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1answer
3k views

Can Artificial Intelligence be used to mine BitCoins faster?

Can Artificial Intelligence be used to find more efficient mining algorithms? Is there only one algorithm that can be used to mine? EDIT: Asking about running the SHA(SHA(block header)) more ...
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2answers
2k views

Bitcoin without mining

Several months ago I've stumbled an interesting question about the Ripple system: How does Ripple solve the double-spend problem? Specifically about how double-spending is solved in Ripple. As you ...
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2answers
1k views

Why does an adversary have to control 50% of the computing power to double spend?

If transactions in a block are valid, in order to add that block in the block chain, a proof of work needs to be found. I have read the bitcoin paper by Satoshi. If the difficulty of the proof of ...
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2answers
2k views

How is it that concurrent miners do not subvert each other's work?

Every time a new block is added on top of block chain, the miners have to restart their work because the next block has to have a proper reference to previous block. Let's suppose that there is some ...
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4answers
378 views

What is the useful work done during the mining of Bitcoin? [duplicate]

What is the work that the computer performs while it does Bitcoin mining? Is it useful work in any case?
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2answers
412 views

What happens to a miner's work when they restart?

I am studying the bitcoin internals and especially the proof-of-work. The proof-of-work is based on the mathematical problem that we have to compute from an input that produces a hash with a certain ...
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1answer
128 views

Would miners have an advantage by proceeding randomly?

If most miners are looking for solving their proof of work in a prescribed order (perhaps preceded by a prescribed way to break down the search space, e.g. by dichotomy); is there not an advantage for ...
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2answers
775 views

Is it possible for the network to stop finding valid blocks?

The hashing problem is by design computationally hard, because SHA-256 hashes are for all intents and purposes random strings with no direct link to their inputs, and there's no (known) way to ...