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Short Answer To add to the already helpful answers here. Simple put difficulty is a scaling parameter it does not have units. Long Answer To understand what is actually is doing requires a little background: A bitcoin hash is comprised of 64 hex characters. Or in other words, 16^64 unique encodings (1.15 * 10^77). The minimum proof of work (PoW) for a ...


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Now, I'm not a math guy, but from what I can gather, this strategy takes up a lot of computing memory. Therefore, my question is - is this strategy theoretically feasible? If it is feasible, SHA256 is broken and we should switch to something else. The whole point of proof-of-work is to find a function for which partial preimages can practically only be ...


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It's not clear what the strategy is. It just says "and solve the system of equations". The entire structure of cryptographic hashes like SHA256 is carefully designed to make doing this as difficult as possible, and there's not even a hint of how to solve that system of equations. This is precisely what ordinary miners do, except they try to solve the ...


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Sure, the protocol could have been designed that way. The benefit would be that a block would be slightly smaller, since it only needs to contain a single address, rather than a full coinbase transaction. However, a benefit of the current system is that miners have the flexibility to pay out their coinbase transaction in some other way than sending it all ...


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Yes, both scenarios are possible. The validity of a block is determined solely by its contents, not by when it is broadcast or received, so the attacker's longer chain is equally valid whether they broadcast it as they go, or all at once. (There is an exception to this principle on testnet because of the 20-minute rule, but that's not relevant here.)


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When a pool gives a miner data to mine it is not data for one specific block, but a template for a block. The miner hashes many variations of this block data to try to find a block that has a hash value below the current target (which is determined by the current difficulty). To calculate the hash of a block on the blockchain given only the data that the ...


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What do the other participants in the network gain from accepting their answers to the puzzle? There are a number of great answers already, but here is another way to look at it: consider flipping this question around. What does a miner lose by mining on block X+1 instead of block X? The answer is: nothing. Assuming an ~equal payout for finding block X ...


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Miners don't mine for fun or out of generosity. They mine because they want to get the block reward and the transaction fees. Clients are programmed to choose the "longest" chain, that is, the one that took the most mining work to produce. Now, say you're a miner who has 1% of the network's hash rate. You're trying to mine block 50,000 when someone else ...


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What prevents that certain miners and the blocks they can contribute to the chain are not ignored? The fact that other miners are building on top of the newly-generated block, but also because they (experimentally?) know that most of the network participants are accepting it. All miners basically mine on top of the newly published blocks because otherwise ...


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"SPV mining" refers to a bad practice where a miner starts hashing a new block on top of an unverified parent block. If the parent block turns out to be invalid due to a double spend or newly activated soft fork, the new block will also be invalid. The term SPV in this case is used because the miner only verifies the headers of the incoming block and then ...


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What do the other participants in the network gain from accepting their answers to the puzzle? Essentially, consensus. As long as a miner controls less than 51% of the network hashrate, they must always try to mine on top of the newest block. If miner A creates block 1000, miner B may ignore it. Let's say B controls 20% of the hashrate. If B continues to ...


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Bitcoin miners are anonymous. There’s no identifying information in blocks that could be used to censor a particular participant. The attributions for miners shown on block explorers are guesswork presented as fact.


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(2) Based on the previous block hash, I calculate the possible block header combinations of the nonce, the version number, the timestamp* and the Merkle root. The goal is to simply find a valid block header which has a lower hash value than the current target. The block header is 80 bytes size: version: 4 bytes. previous hash: 32 bytes. merkle root: ...


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