The chart is misleading for most cryptocurrencies.
The "1h Attack Cost" is calculated from the rentable hashrate from NiceHash, but you should pay attention to the "NiceHash-able" column that says how much hash you can actually rent.
While you'd think you could attack Ethereum for only 1.5 million dollars, you can only rent 7% of that hashrate, so you can't get the required >50% you'd need to pull of the attack.
Even if you cannot conveniently rent the required hardware from a provider, it still seems rather concerning that behemoths like Ethereum could be brought down rather easily with an investment of a few million dollars (especially by government actors for example).
Perhaps I misunderstand the table in the article or the impact of a 51% attack however.
> you can only rent 7% of that hashrate, so you can't get the required >50% you'd need to pull of the attack.
Is this 7% per customer or aggregate per blockchain? Ie could I set up a dozen or so companies to each have a few percent of NiceHash and obtain the 51% that way?
I see a lot of people saying that there aren't a lot of attacks that having a 51% enables. I'd like to understand that a little bit better. Are there markets where you can short-sell cryptocurrencies? If so, mightn't you be able to turn a good profit by shorting one of these smaller coins (say Quarkchain at $30/hour with a market cap of $116M), then launching a 51% attack for a week or two, in the hopes of tanking the coins value? That would only cost you $5k per week.
Previous discussion from the posting of this site three years ago (including by the dev who built this website). Some of which covers NiceHash topic and also other problems you're going to phase when trying to do a 51% attack + profit out of it.
For the upcoming POS Ethereum chain (which is still being worked on!), the current cost is around $15 billion. And that increases as more stakers get online.
Vitalik Buterin just explained that a few days ago and provided that number.
So I'm very sceptical of these numbers on that website or I'm not able parse what it tries to say.
A very different number for a 51% attack against a completely different consensus mechanism does not seem like it should provoke skepticism. Especially since resistance against 51% attacks is a specific benefit of that new mechanism. Are you proposing that the website plops down that $15B number for a consensus mechanism that isn't even operational yet?
(I think there are other things that are misleading, notably that it measures what Nicehash could do, but not all of its capacity is actually for rent at any given time.)
That’s a small sum for many nation states but good to know we only have to worry about nations or conspiracies. Do you have a link to more information about this?
As some point out this is based on the price of buying hashing power from NiceHash, which in case of Ethereum can at most cover 7% of Ethereums hashing power. And costs are different if you need to buy/invest in the hardware to pull a 51% attack furthermore even if you "could just rent more" you would be adding hashing power to the Ethereum network increasing when 51% is hit as you don't replace hashing power, and then the more you buy the more "pricey" hashing power becomes... that is if you can even get the required amount of hashing power in current economics. (E.g. if Etherums current hashing power is 100 then you need >50 hashing power, but you need to get >50 hashing power OF that 100 hashing power if you just add 50 hashing power you now have a total hashing power of 150 and as such need 75. So if you control 0 of the current hashing power and have no way to reduce that you need to add >100% of the hashing power to controll >50% of the final hashing power...).
The 51% attacks only allow double spend attacks, you can't "steal" money and the attacks sooner or later will be noticed and might be reversed.
Then even if you run a 51% attack it's still a crime in more or less any country and controlling 51% of hashing power and staying truly anonymous isn't easy, given how much electricity and hardware PoW consumes. (But it's viable, through maybe only if you are state backed.)
The most feasible way to pull of a 51% attack on a larger network IMHO is by hacking multiple hashing pools.
Through like the article mentions it's a completely different thing for smaller networks. It also shows nicely why you need increasingly more hashing power the more value moves through your network (it's a counter argument to people defending PoW by saying you could just do more transactions per block).
It's also why some new chains which use PoS start out with "a farming game" where people already "stack" money before the crypto currency is worth any money (and get money based on that when "it goes live"). Because with that you can start with a already reasonable secure system.
> I'm not able parse what it tries to say.
1. Small crypto currencies are not so secure (if not build on another chain).
2. PoW is not as grate as some people make it out to be (IMHO PoW a terribly solution but it probably was the best terrible solution when Bitcoin was made).
3. And I would add: PoW based Currencies hashing cost and marked value needs to be in balance. (For PoS it's the stacked amount and marked value, which is IMHO easier to archive as it doesn't require additional factors like access to hardware and cheap electricity.)
Would a 1 hour attack have any long-term effect though? Once the attack stops, won't the legitimate chain catch up to and surpass the one that contains the false transactions? If the only effect of the attack is to have some false transactions be on the dominant chain for a few hours, the damage isn't that much different than Visa being down for a few hours, so long as you are able to either detect that the attack is happening, or just always be aware you need to wait a few hours for things to fully settle.
Isn't the entire point of blockchain to automatically prove what the consensus is? If there is a fool-proof off-the-chain way to figure out which is the "legitimate" fork, what is the point of blockchain?
You can't rent that algorithm on the market they are calculating the spot rates for this from; you can come at this in another direction by asking "how much profit would I have to buy off of someone else to convince them to lend me their mining equipment", and we could quibble over whether that would provide more accurate results (I think it would), but I appreciate where the author of this site is coming from: this is how much it might cost to rent this much power off an existing open market for algorithms (which doesn't bother with Bitcoin as that is mined with specialized hardware and this kind of spot market doesn't apply very well).
Bitcoin equipment is specilaised to mining. You'd have to rent 51% of all mining eqipment for an attack, at which point you wouod destroy the value of bitcoin and make the mining eqipment you've just rented worthless. Why would anyone rent to you in that case?
So you'd have to buy the equipment, which is a gradual process, would be extremely expensive and would be noticed.
Because the attack surface is low. You can only stop transactions from happening (by mining an empty blog). You can’t change the past. Hence not worth it? Unless you can make a big purchase using the coin and then change history? There are still checkpoints implemented by clients so forcing the network to go backwards might be hard. So yeah POW doesn’t give you much attack scenarios after all.
You're missing some details about how mining works. "Miners" don't produce blocks; they just do hashing; the mining pools generate the blocks. When you rent mining capacity from NiceHash you can point it to your own pool (full node) to do whatever you want.
Just because people try to be decoupled from the government doesn't mean laws don't apply to them.
Also as a side not operating a mixer without taking protocol about who used it when in which way is pretty clear cut money laundering. Hence why mixers are either exchanges which take your personalities or operated as much anonymous as possible and from countries in which they believe they can avoid the law. (EDIT: Yes there probably are people which operate a mixer without such precautions, and they might end up pretty bad if a country purses money laundering charges and it doesn't even need to be their country.)
"How is the attack cost calculated?
Using the prices NiceHash lists for different algorithms we are able to calculate how much it would cost to rent enough hashing power to match the current network hashing power for an hour. Nicehash does not have enough hashing power for most larger coins, so we also calculated what percentage of the needed hashing power is available from Nicehash.
Note that the attack cost does not include the block rewards that the miner will receive for mining. In some cases this can be quite significant, and reduce the attack cost by up to 80%."
[+] [-] lawn|4 years ago|reply
The "1h Attack Cost" is calculated from the rentable hashrate from NiceHash, but you should pay attention to the "NiceHash-able" column that says how much hash you can actually rent.
While you'd think you could attack Ethereum for only 1.5 million dollars, you can only rent 7% of that hashrate, so you can't get the required >50% you'd need to pull of the attack.
[+] [-] ProjectArcturis|4 years ago|reply
[+] [-] osigurdson|4 years ago|reply
Perhaps I misunderstand the table in the article or the impact of a 51% attack however.
[+] [-] yardstick|4 years ago|reply
Is this 7% per customer or aggregate per blockchain? Ie could I set up a dozen or so companies to each have a few percent of NiceHash and obtain the 51% that way?
[+] [-] tkfu|4 years ago|reply
[+] [-] miduil|4 years ago|reply
https://news.ycombinator.com/item?id=17173051
[+] [-] kerng|4 years ago|reply
Vitalik Buterin just explained that a few days ago and provided that number.
So I'm very sceptical of these numbers on that website or I'm not able parse what it tries to say.
[+] [-] lvh|4 years ago|reply
(I think there are other things that are misleading, notably that it measures what Nicehash could do, but not all of its capacity is actually for rent at any given time.)
[+] [-] shoto_io|4 years ago|reply
Sounds like any other IT project!
[+] [-] littlestymaar|4 years ago|reply
Just curious, do we have an idea of how much Buterin himself holds?
[+] [-] gregwebs|4 years ago|reply
[+] [-] dathinab|4 years ago|reply
The 51% attacks only allow double spend attacks, you can't "steal" money and the attacks sooner or later will be noticed and might be reversed.
Then even if you run a 51% attack it's still a crime in more or less any country and controlling 51% of hashing power and staying truly anonymous isn't easy, given how much electricity and hardware PoW consumes. (But it's viable, through maybe only if you are state backed.)
The most feasible way to pull of a 51% attack on a larger network IMHO is by hacking multiple hashing pools.
Through like the article mentions it's a completely different thing for smaller networks. It also shows nicely why you need increasingly more hashing power the more value moves through your network (it's a counter argument to people defending PoW by saying you could just do more transactions per block).
It's also why some new chains which use PoS start out with "a farming game" where people already "stack" money before the crypto currency is worth any money (and get money based on that when "it goes live"). Because with that you can start with a already reasonable secure system.
> I'm not able parse what it tries to say.
1. Small crypto currencies are not so secure (if not build on another chain).
2. PoW is not as grate as some people make it out to be (IMHO PoW a terribly solution but it probably was the best terrible solution when Bitcoin was made).
3. And I would add: PoW based Currencies hashing cost and marked value needs to be in balance. (For PoS it's the stacked amount and marked value, which is IMHO easier to archive as it doesn't require additional factors like access to hardware and cheap electricity.)
[+] [-] GhostVII|4 years ago|reply
[+] [-] remram|4 years ago|reply
[+] [-] samfisher83|4 years ago|reply
[+] [-] saurik|4 years ago|reply
[+] [-] ClumsyPilot|4 years ago|reply
So you'd have to buy the equipment, which is a gradual process, would be extremely expensive and would be noticed.
[+] [-] Closi|4 years ago|reply
Out of interest why aren’t these attacks more common? (Not even for profit, even just for bragging rights)
[+] [-] sktrdie|4 years ago|reply
[+] [-] JustResign|4 years ago|reply
It assumes you can rent this capacity via NiceHash, but the whole point of a 51% attack is to run _different code_ on the majority of nodes.
Surely NiceHash would rent you capacity running the vanilla e.g. Ethereum code, rather than your fork?
To assume otherwise basically makes NiceHash remote code execution as a service.
[+] [-] wmf|4 years ago|reply
[+] [-] matheusmoreira|4 years ago|reply
[+] [-] bcanzanella|4 years ago|reply
[+] [-] osigurdson|4 years ago|reply
[+] [-] WanderPanda|4 years ago|reply
[+] [-] dathinab|4 years ago|reply
Just because people try to be decoupled from the government doesn't mean laws don't apply to them.
Also as a side not operating a mixer without taking protocol about who used it when in which way is pretty clear cut money laundering. Hence why mixers are either exchanges which take your personalities or operated as much anonymous as possible and from countries in which they believe they can avoid the law. (EDIT: Yes there probably are people which operate a mixer without such precautions, and they might end up pretty bad if a country purses money laundering charges and it doesn't even need to be their country.)
[+] [-] TheTester|4 years ago|reply
Note that the attack cost does not include the block rewards that the miner will receive for mining. In some cases this can be quite significant, and reduce the attack cost by up to 80%."
[+] [-] pornel|4 years ago|reply
And it's kinda scary that coins that claim to have millions of dollars in market cap can be attacked for a price of a sandwich.
[+] [-] ClumsyPilot|4 years ago|reply
In the same time preiod we have seen mutiple hacks again banks, governments and the military.
The proof is in the pudding
[+] [-] belter|4 years ago|reply
However its is stunning: Ethereum market cap $313.09 B ( yes with a B ), and you can pull off a 51% Attack for 1.5 million dollars ?
Litecoin market cap $12.51 B and you can pull off a 51% Attack for 250 thousand dollars ?
It seems Vitalik Buterin gives frequent interviews. Anybody aware if has been asked about this ?
Can any of you with comment on the technical validity of this info. Because frankly, if this all it takes, I am tempted :-)