78 votes
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Why did Satoshi design Bitcoin to be mineable only on specialized hardware, if the goal was decentralization?

Bitcoin was not designed to only be mineable with specialized hardware. When Bitcoin was created in 2009, ASIC miners did not exist, SHA256d ASICs did not exist. Even GPU mining software did not exist ...
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  • 60.4k
59 votes
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What is Gas Limit in Ethereum?

In Ethereum, gas is a measure of computational effort. To each operation, a fixed amount of gas is assigned (e.g. adding two numbers costs 3 gas, calculating a hash costs 30 gas, sending a transaction ...
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  • 1,896
40 votes

51% attack - apparently very easy? refering to CZ's "rollback btc chain" - How to make sure such corruptible scenario can never happen so easily?

Disclaimer: I believe this question may be primarily opinion-based and not very appropriate for this site, but there are a number of technical misunderstandings that can be clarified along with it, so ...
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38 votes
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Can bitcoin exist without miners?

if in the coming years the difficulty increases so much that mining is no longer profitable That's not really possible. The mining power is set so that the miners need 10 minutes in average to mine a ...
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  • 2,037
32 votes
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Why do miners go offline?

One of the most common reasons for which miners go offline is when their profitability drops below the cost of electricity - this could either be the result of the BTC price dropping, or their local ...
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  • 16.4k
22 votes
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What does it mean for a cryptocurrency to be ASIC-resistant?

It means that there will be no significant speedup by implementing the algorithm in an ASIC, as compared to a CPU based implementation. This is usually achieved by requiring a lot of memory, which ...
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20 votes
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Why doesn't the same miner always win?

Mining is not won by the miner with the "strongest ability to solve the block". Mining is a random progress-free process. Each block candidate independently has a tiny chance to be a valid ...
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  • 62.3k
19 votes
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Supermajority to prevent 51% attack?

The 51% attack is emergent behavior of the system. It's not because there's a "50%" buried somewhere in the protocol that can just be changed to 60% or 75%. Someone with more hashing power than ...
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16 votes
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So I mined a block, but why would other nodes accept my mined block?

The incentive to mine on the currently longest chain is that there is a risk to the dishonest miner that honest, non-mining nodes may have already propagated the first block and hence reject and not ...
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15 votes

What happens if two miners mine the next block at the same time?

What Nicolai said is not completely right. The network would decide which one is the main chain according to the following block mined. Let's assume that block A and B are mined at almost the same ...
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  • 151
15 votes

What does it mean for a cryptocurrency to be ASIC-resistant?

An ASIC is another way of running a program or calculation or what have you (in our case mining) using a PCB/Hardware instead of Software running on a general purpose computer. GPUs are technically ...
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  • 261
15 votes
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How is a block header hash compared to the target (bits)?

How to calculate the target from bits Let's start with a block-header, always 80-bytes that looks like this: ...
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  • 7,619
14 votes

Why do we need Proof of Work in bitcoin?

Proof of Work (PoW) basically makes sure that miners don’t cheat. There is no way to trust that everyone in the network is honest, so there has to be some way to prevent miners from creating new ...
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  • 141
14 votes
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Why search for a nonce linearly (+1) vs searching only even or odd nonces?

A 2X rate with a 50% chance of missing a winning nonce is no advantage at all. Incrementing the nonce is the easiest mechanism of choosing the next nonce to try, so you try the most nonces per second ...
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13 votes

Why can't they use super computers to mine all the bitcoins?

A supercomputer is way slower than mining with ASICs. A supercomputer only has much CPU power, not even GPU power and ASICs are way more powerfull than GPUs. ASICs represent the hashing algorithm as ...
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13 votes
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What can be done to slow/prevent mining centralization?

Asking how to prevent the mining industry from being centralized into places with low electricity costs is like asking how to prevent the shipping industry from being centralized into cities that are ...
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  • 8,724
13 votes

Why did Satoshi design Bitcoin to be mineable only on specialized hardware, if the goal was decentralization?

GPU-mineable cryptos are arguably more decentralized. Sure, but in a bad way. Say you want to attack or compromise bitcoin. You have to buy ASICs to do it. You could use GPUs or CPUs, but you would ...
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12 votes
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Why do we need Proof of Work in bitcoin?

Imagine I have 1 bitcoin. And imagine I can form a transaction to send that bitcoin to Alice or I can form a transaction to send that bitcoin to Charlie. Now, what stops me from forming both ...
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12 votes
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Download single and specific block for study purposes

However this is JSON, I imagine I can't use it to verify the nonce. You can. You can build the block header using the data at the beginning of the JSON object and then hash that. Of course it would ...
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  • 60.4k
12 votes
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Understanding POW and transactions

This is a common misconception: mining is progress free. Yes, it may take 10000 hashes in your example on average to find a block, but this only means that every attempt has 1/10000 chance of being a ...
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11 votes
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Probablity Distribution of mining

The time between consecutive blocks follows the exponential distribution, with mean (roughly) 10 minutes. This means that the variance is 100 minutes^2.
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11 votes
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What Value does mining provide?

As you mentioned, bringing coins into the network is one of the main purposes of mining. But this reward is just an incentive to do the other more important part of mining: 'processing' transactions. ...
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  • 13.7k
11 votes

What is a nonce?

Nonce is a 32 bit arbitrary random number that is typically used once. In Bitcoin's mining process, the goal is to find a hash below a target number which is calculated based on the difficulty. Proof ...
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11 votes
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Do miners validate each other's blocks?

Mining is a random, progress-free process. Miners are essentially attempting to find a partial pre-image of a hash. Each new (valid) block candidate has exactly the same minuscule chance of yielding a ...
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  • 62.3k
11 votes

How would faster blocks cause mining centralization?

Why faster blocks? This conversation often starts with someone pointing out that shortening the block interval would allow for a quicker first confirmation, reduce variance in mining revenue, and ...
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  • 62.3k
10 votes

51% attack - apparently very easy? refering to CZ's "rollback btc chain" - How to make sure such corruptible scenario can never happen so easily?

(adding some color) Some discussion I saw suggested that people promoting this believed they only needed to achieve >50% hashpower, which caused them to overestimate the feasibility. Reorging with ...
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  • 7,429
10 votes
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Why is the winner of Pow different everytime?

Because each miner may select the transactions (and the order in which they are included) in each block. Also, they do not all start on the same exact nonce, in fact they are changing more than just ...
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  • 7,030
10 votes
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Bitcoin migrating to a ASIC resistant mining algorithm like RandomX used on Monero

The bitcoin community would have to decide that they don't particularly care about having significant security anymore. ASIC-resistance weakens the security of proof of work chains because it ...
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10 votes
Accepted

Why are there more than two transaction outputs in a coinbase transaction?

A coinbase transaction can have as many outputs as the miner who created it wants. You may see that there are not just one output for the reward, sometimes there are multiple outputs so that the ...
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  • 60.4k
9 votes

How does proof-of-stake "mining" work?

For Peercoin specifically, PoW and PoS blocks are independent. Just as you're betting your consumed electricity and CPU-time vs. the possible PoW-blok's reward, in the PoS blocks you're betting your ...
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  • 2,128

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