Questions tagged [block-withholding]

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How is block-solution-withholding a threat to mining pools?

If I understand the technical process (for most mining pools) correctly, a participant in a mining pool is given block data to combine with a nonce to try to solve the block. If they get close (but not close enough to give the actual solution) to…
Highly Irregular
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What is a block withholding attack?

How can a block withholding attack be performed, what would be its purpose and who is it a danger to? Edit: when I posted this I was thinking about withholding a block you mined in a pool. But withholding blocks can form the basis for many different…
Dr.Haribo
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How does a pool know work has been done

I have not been able to find any method that pools use to verify you've done the work you say you did. So if someone does a solution withholding attack but without actually knowing what the solution is in a PPS pool then can't this attack just get…
David
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How do mining pool payout methods affect the cost of executing a block withholding attack?

I'm wondering how each payout method (PPS, DGM, PPLNS, Proportional, etc) influences the cost of executing a block withholding attack. Does it matter how the payout method places variance between pool and miners? With DGM this is a setting that can…
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What verb best describes "causing another block to become stale"?

For example, suppose I'm selfish mining; you publish a block and then I immediately publish two, what did I do to your block? Similarly, if I'm executing a double-spend attack, my goal is to ?___? the block containing the transaction standing in the…
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What is the difference between Selfish Mining and Block Withholding attacks?

I found contradicting information about these two attacks. My understanding is roughly this: Selfish mining is a strategy followed by a miner/pool, in which it doesn't publish new blocks in order to obtain a secret fork which is longer than the…
FedFranz
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Known cases of block-withholding attacks

At the moment I am doing a course about Bitcoin. The topic of the last session was the block-withholding attack and the course (being from 2014) claimed that there are no known attacks so far. Is block-withholding a strategy used by mining pools in…
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Possible to include a per miner transaction to prevent withholding and independent rebroadcast of a solved block?

Update: This is a bad idea because it simply won't work, but it did help me understand what happens between a Miner and a Pool. And if you missed it in the comments, read @Meni's PDF for a threat and profitability analysis of pools. Is it feasible…