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BTC Endgame

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Re: BTC Endgame

#161

Post by beaner »

nostrademons wrote: post #17

You don't need a DoS attack under the assumptions of this project. It's already assumed that you control ~80% of hash rate, so you execute a 51% attack that mass double-spends coins and destroy all confidence in the integrity of the currency. Poof, nobody uses it. Note that China already controls ~65% of Bitcoin hash rate, so if they wanted to execute this right now, they probably could. That they haven't is one reas…

> so you execute a 51% attack that mass double-spends coins

51% attacks don't double-spend coins. It just means you get to control which blocks are accepted, it doesn't mean you can violate the rules.

Re: BTC Endgame

#162

Post by Laforet »

wruza wrote: post #153
fanciestManimal wrote: post #61

Earlier quoted context omitted.

It's an unsolved problem, and all solutions would require a majority of the mining pool to get on board. You could periodically increase the block size, splitting the transaction fee among more transactions. Although larger blocks make it more difficult to produce hashes, so more power would be consumed, thus increasing the transaction fees further. You could change the block reward such that there's a larger block r…

periodically increase the block size, splitting the transaction fee among more transactions. Although larger blocks make it more difficult to produce hashes Couldn’t they simply lower the baseline difficulty along with a block size? Edit: and wouldn’t difficulty drop automatically in this case?

Bitcoin is best understood as a timestamping service that signs up to 1MB of information every 10 minutes. Recording monetary transactions is only one of its applications.

The 10 minute interval is an important part of the consensus mechanism as it has been proven secure both theoretically and practically. With shorter block interval and odds of orphan blocks and small chain reorgs would become more likely and this could break some aspects of security model such as zero-conf transactions.

By the way larger blocks don't take longer to hash - only the fixed size header is used for PoW. However larger or more blocks do require more bandwidth and storage to process.

Re: BTC Endgame

#163

Post by curyous »

beaner wrote: post #161
nostrademons wrote: post #17

You don't need a DoS attack under the assumptions of this project. It's already assumed that you control ~80% of hash rate, so you execute a 51% attack that mass double-spends coins and destroy all confidence in the integrity of the currency. Poof, nobody uses it. Note that China already controls ~65% of Bitcoin hash rate, so if they wanted to execute this right now, they probably could. That they haven't is one reas…

> so you execute a 51% attack that mass double-spends coins 51% attacks don't double-spend coins. It just means you get to control which blocks are accepted, it doesn't mean you can violate the rules.

Double-spending doesn't change the rules, it changes where coins get sent, so you can rip-off the original recipient.

Re: BTC Endgame

#164

Post by asdfasgasdgasdg »

3np wrote: post #152
generalizations wrote: post #51

Earlier quoted context omitted.

I'd make a wild guess that when parent is talking about 'control', they mean that if a miner is located within China, the Chinese government has the ability to put a gun to that miners head and tell them what to do.

"The mountains are high and the Emperor is far away". Neither mining pools (who practically have the actual power over transaction inclusion an ordering) nor the miners are cooperating. I'm also certain the CCP wouldn't be practically able to locate and control all of them that easily.

The emperor is only a few tens of milliseconds away, no matter where you are in China.

Re: BTC Endgame

#165

Post by shawnz »

hanniabu wrote: post #143
shawnz wrote: post #123

Earlier quoted context omitted.

Miners don't control the price. If a PoS coin became valued, they'd be leaving free money on the table to ignore it. And if Bitcoin became devalued, the mining rate would drop to match (otherwise they'd be spending in excess of the reward on electricity)

Miners don't control the price but they control the upgrade. Why would the miner vote (with their hashpower) to upgrade to a PoS consensus and kill their business?

They don't control the upgrade: new miners can simply come in to take the free rewards on the new coin if the existing ones refuse to do it.

All that matters is the market's valuation of the currency: it would be irrational for miners to do anything except expand until their costs nearly match the reward.

Re: BTC Endgame

#166

Post by ALittleLight »

3np wrote: post #152
generalizations wrote: post #51

Earlier quoted context omitted.

I'd make a wild guess that when parent is talking about 'control', they mean that if a miner is located within China, the Chinese government has the ability to put a gun to that miners head and tell them what to do.

"The mountains are high and the Emperor is far away". Neither mining pools (who practically have the actual power over transaction inclusion an ordering) nor the miners are cooperating. I'm also certain the CCP wouldn't be practically able to locate and control all of them that easily.

I'd assume their intelligence services are identifying miners now while the miners don't have incentive to hide. If China wanted to strike at bitcoin they could do it in one fell swoop.

Re: BTC Endgame

#167

Post by polyomino »

WJW wrote: post #15
paulgb wrote: post #2

The linked Medium posts have a bit more content https://joekelly100.medium.com/how-to-kill-bitcoin-part-1-is... Note that this is from last July, when the price of BTC was significantly lower and thus the price of the attack is likely higher now. That said, this becomes more feasible in the long-run when mining is purely funded by transaction fees. Something I don’t see talked about much is the fact that, although Bi…

I always wondered about that and perhaps someone here can explain. After bitcoin reaches its "full" volume, mining rewards will go away and the only way miner income can stay the same is if transaction fees rise to match. Since the competition of miners basically converges to "block reward is equal to electricity cost equivalent", this would mean transaction costs increase to an insanely huge amount. Not paying the l…

Transactions will move to lightning, and since this allows multiple transactions to be aggregated into a single on-chain transaction, fees will be higher per transaction on chain.

Re: BTC Endgame

#168

Post by Retric »

inopinatus wrote: post #144
nyolfen wrote: post #141

Earlier quoted context omitted.

if 51% of hash power were located in the US, the statement would have been about the US. it is not something special about china that makes this the case, only the fact that it is a sovereign state with the means and will to control activity in its territory, just like every other functioning state. one could also make the case that china might be more likely to intervene in such a way in the economic affairs of its…

No, China is not a person with a single will. The assumption/assertion that the mining equipment may as well all be sitting under MSS guard in Beijing is horsecrap.

For small scale miners in China it might be a different story.

However, if Xi Jinping decided to crush Bitcoin for whatever reason large scale mining in China, which is well past 50%, would quickly do what he wanted. As such he has de facto control over Bitcoin, though I personally doubt it’s something he would do.

Re: BTC Endgame

#169

Post by DSMan195276 »

AffableSpatula wrote: post #94
DSMan195276 wrote: post #80

Earlier quoted context omitted.

I don't understand what you're getting at, I was pointing out why Bitcoin hasn't moved to PoS even if it may actually be better.

You're right, I totally misread what you said. I think the answer to what you actually said is; miners don't control consensus on the network - it's not up to them, it's up to fullnodes/users who can change the ruleset whenever they want.

You're good :)

And I agree to a point, but miners are the ones that effectively run the network, and there aren't actually all that "many" of them. Without the existing miners willing to contribute the existing network would fall apart. PoS is an interesting situation because it technically makes the miners unnecessary, but obviously the miners are going to say "no" and just keep going with the existing Bitcoin. It would just create another Bitcoin Cash situation effectively, which is a lot less appealing than if everybody switched to PoS and left nobody using the old version.

Re: BTC Endgame

#170

Post by Vecr »

nine_k wrote: post #81
trevelyan wrote: post #39

Distributed Proof-of-Work is not vulnerable to this: https://org.saito.tech/eliminating-51-attacks-in-proof-of-wo... The community of users simply attaches harder cryptographic proofs to their transactions, forcing up the cost of producing empty blocks. The approach is capable of bankrupting nation-states as a side-effect of eliminating 51% attacks.

Why won't it make transactions prohibitively expensive? Each transaction needs a trustless agreement of many, many nodes.

Not unless the block sizes down, or the block times/ block/transaction relaying latency go way up. The great firewall of China might cause some issues, but in theory it should not get worse.
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