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Bitcoin mining hash rate drops as blackouts instituted in China

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Re: Bitcoin mining hash rate drops as blackouts instituted in China

#61

Post by arcticbull »

c54 wrote: post #54
2bitencryption wrote: post #14

> Significantly, the Xinjiang and Sichuan regions of China combined account for more than 50 percent of the overall Bitcoin mining hash rate I don't get it, doesn't this effectively mean China can force a 51% attack by just strongarming the pools that operate there?

> doesn't this effectively mean China can force a 51% attack by just strongarming the pools that operate there? Yes, in theory. There's a coordination problem to get all the pools to do what you want, but if they (or anyone) could pull that off, then yes. So then what happens? If a single entity controls >50% of the hash power of the network, they could start finding blocks with arbitrary (invalid) transactions and a…

> Yes, in theory. There's a coordination problem to get all the pools to do what you want, but if they (or anyone) could pull that off, then yes.

A strongly worded memo from Xi should sort that out, unless of course they want to switch from mining coins to mining minerals. They're in the right region already.

Re: Bitcoin mining hash rate drops as blackouts instituted in China

#62

Post by mrits »

gruez wrote: post #40
mrits wrote: post #32

Earlier quoted context omitted.

I'm not sure about that. Most miner operations in the US run only a fraction of the day to take advantage of electrical savings that a lot of operations in China wouldn't be doing. So if miners started returning higher yields we would output a larger hash rate. If we actually needed to protect against a 51% attack we could ramp up accordingly.

The difficulty adjustment only happens every 2016 blocks (~2 weeks), so the higher yields wouldn't happen unless they're down for an extended period of time.

That is correct but I don't see why you are pointing it out.

Re: Bitcoin mining hash rate drops as blackouts instituted in China

#63

Post by ChainOfFools »

gruez wrote: post #52
ChainOfFools wrote: post #48

Earlier quoted context omitted.

the consensus vote to activate sw2x on existing BTC network was an in-band mechanism, and set to some super impossible threshold like 95 or 99% to activate a protocol change. this is a different situation, where an out of band entity can selectively shut off a significant fraction of hashpower, and unlike the weedy obscurity of an architectural spat between largely unknown (by the mainstream) such a move would (indee…

>the consensus vote to activate sw2x on existing BTC network was an in-band mechanism, and set to some super impossible threshold like 95 or 99% to activate a fork. Source for this? I searched around and the target was 80%. https://www.weusecoins.com/what-is-segwit2x/ > such a move would (indeed, will) make major waves in mainstream Joe Pension Fund/ Number Go Up news, who will not be familiar with nor interested in…

> Their SegWit code, defined by BIP141, activates if 95 percent of hash power within a single difficulty period of about two weeks signals readiness before November 15th.

Re: Bitcoin mining hash rate drops as blackouts instituted in China

#64

Post by arcticbull »

foepys wrote: post #39
bpodgursky wrote: post #29

Earlier quoted context omitted.

It seems far easier and cheaper to keep the nukes running and just stockpile, like, a suitcase worth of uranium.

And in the event of an attack you just hope they won't target nuclear power plants to recreate Chernobyl and Fukushima?

Nuclear reactors are very much hardened against such attacks, and of course, those were both very different situations. No need to spread FUD about the safest form of electricity in the entire world in terms of deaths per TWh. [1] It's also roughly zero carbon.

You know the worst nuclear accident, Chernobyl, killed 4000 people in the full course of time - and we've learned a ton since then. Fukushima killed 1 person.

On the other hand the worst hydro accident, Banqiao Dam, killed 200,000 people instantly. [2] Such an outlier it's frequently excluded from all analyses on hydro safety. No such luck for the Soviets though.

I know what I'd target for maximum effect.

[1] https://www.statista.com/statistics/494425/death-rate-worldw...

[2] https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure

Re: Bitcoin mining hash rate drops as blackouts instituted in China

#65

Post by bpodgursky »

foepys wrote: post #41
bpodgursky wrote: post #17

Earlier quoted context omitted.

Arguments about Germany's energy independence would be far more compelling if they were not, for example, currently building giant pipelines to import Russian natural gas. https://en.wikipedia.org/wiki/Nord_Stream

That's mostly for heating, though. Heat pumps are being increasingly used in new homes but nearly all homes older than 10 years are using gas or oil furnaces. Electricity prices are also very high, amongst the highest in the world, so heat pumps aren't as cheap to run as in other countries. It's definitely a problem that needs to be fixed, potentially within the next 30 years because that's the timeframe where the la…

But electricity would be cheaper... offsetting imported natural gas... if they left the nuclear power plants on.

Re: Bitcoin mining hash rate drops as blackouts instituted in China

#66

Post by jabbany »

2bitencryption wrote: post #14

> Significantly, the Xinjiang and Sichuan regions of China combined account for more than 50 percent of the overall Bitcoin mining hash rate I don't get it, doesn't this effectively mean China can force a 51% attack by just strongarming the pools that operate there?

In theory yes, but in practice it's rather infeasible to do 51% attacks IRL --- the main constraint is the people not the math.

A 51% attack mainly lets you double spend, so you have to: (1) get a lot of coins and spend them on something (2) start mining a fork where that spending didn't happen (but other real transactions continue to happen) --- your hash power will now need to be dedicated to this new fork at the exclusion of the old "real" fork since all future hashes will diverge (3) wait until the thing you paid for with coins can no longer be "taken back", all while continuing efforts on the alternate fork (4) do the 51% attack to swap out the old "real" fork with your new fork where you never bought the thing, thus keeping the thing _and_ the coins you spent on them (5) all this needs to be balanced with the opportunity cost had you just continued mining on the real chain...

Such an attack would trigger immediate attention since at (2) the main chain would suddenly see a drop in contributions. Also realistically most things you can purchase with coins (like fiat or other goods/services) can be relatively easily "taken back" unless a considerable amount of time is spent to launder them --- say if you "buy" a car with crypto and reverse the transaction, what you've really done is just stolen a car with a lot of extra steps... Which means your only real viable path is to redeem for some other cryptocurrency... Now given that a big attack just happened on the largest market cap crypto, there's a pretty good chance the other coins are going to take a hit and exchanges might even temporarily limit activities while this situation is "investigated", greatly reducing what you can actually do at the end of the day.

This kind of thing is more reasonable on the smaller market cap "meme" coins where you can just exchange them for for a mass-market crypto.

Re: Bitcoin mining hash rate drops as blackouts instituted in China

#67

Post by yuvadam »

fouc wrote: post #51
paulmd wrote: post #50

Earlier quoted context omitted.

> if you don’t touch your coins, no one can take them away from you. (A 51% attack can’t reassign coins.) it can't generate new unsigned transactions but it can roll back the network to a state when someone else owned those coins. from a practical perspective there is no difference, you no longer have those coins.

there's a limit to how far it can roll back the network, it probably wouldn't be able to roll back more than a few days..

"Rolling back" the network means successfully creating a new longest chain that forks off of an arbitrary old block.

The further back in time you to "rollback" to, the less probable it is for the 51% to successfully mine all those needed blocks to get up to par with the existing longest chain.

Realistically speaking, this sort of attack is highly improbable.

Re: Bitcoin mining hash rate drops as blackouts instituted in China

#68

Post by arcticbull »

gruez wrote: post #52
ChainOfFools wrote: post #48

Earlier quoted context omitted.

the consensus vote to activate sw2x on existing BTC network was an in-band mechanism, and set to some super impossible threshold like 95 or 99% to activate a protocol change. this is a different situation, where an out of band entity can selectively shut off a significant fraction of hashpower, and unlike the weedy obscurity of an architectural spat between largely unknown (by the mainstream) such a move would (indee…

>the consensus vote to activate sw2x on existing BTC network was an in-band mechanism, and set to some super impossible threshold like 95 or 99% to activate a fork. Source for this? I searched around and the target was 80%. https://www.weusecoins.com/what-is-segwit2x/ > such a move would (indeed, will) make major waves in mainstream Joe Pension Fund/ Number Go Up news, who will not be familiar with nor interested in…

> Fair point, given how the markets reacted to this drop in hashrate.

What makes you think the market reacted to the drop in hash rate? A 20% move is pretty typical in crypto. IMO this is more likely due to Bitcoin not having moved in price in almost 2 months (it's below its 2/18 price now, by a lot). People moved their get-rich-quick energy over to Doge. And once that sputtered out, they tried to cash out.

Tether by the way, had its two biggest outflow days ever on Thursday and Friday (200 and 300M respectively via the Kraken USDT:USD pair). If Tether is actually just backed by crypto and hope as we suspect, they'd have had to sell crypto to refill their depleted cash reserves. To be clear this is pure speculation.

Another possibility is the market is reacting to all the Coinbase executives dumping massive quantities of equity on retail bag holders, signaling a potential top.

Since all cryptos are dumping, primary and alt, it's probably a more systemic issue.

Re: Bitcoin mining hash rate drops as blackouts instituted in China

#69

Post by Romanulus »

taneq wrote: post #8
Lx1oG-AWb6h_ZG0 wrote: post #2

> the National Mine Safety Supervision Bureau has reported three recent coal mine accidents, including an April 10 “water penetration accident” in Xinjiang that caused 21 people to be trapped. > Significantly, the Xinjiang and Sichuan regions of China combined account for more than 50 percent of the overall Bitcoin mining hash rate This is horrific on so many levels, I’m not even sure where to begin. My heart goes ou…

> those poor miners slaving away for... what? Bitcoin, apparently.

Bitcoal.

Re: Bitcoin mining hash rate drops as blackouts instituted in China

#70

Post by idownvoted »

pizzapill wrote: post #45
ekianjo wrote: post #38

Earlier quoted context omitted.

Nope Germany is massively relying on nuclear energy produced by its neighbors.

2002 was the last year Germany imported more power than it exported: https://de.statista.com/statistik/daten/studie/153533/umfrag...

Ah Sweet, the old “exportweltmeister” scam never seems to get old.

Germany is exporting so much energy because (and only because) without the base load provided by conventional power plants it’s energy grid routinely is on the brink of collapse, whenever there are weather based shifts in renewable energy production.

This causes the electricity price to routinely go negative because our neighboring countries don’t want to have it either.

What a failure. And what a failure that people still fall for that exportweltmeister lie

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