Cost of a 51% attack for different cryptocurrencies?
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Re: Cost of a 51% attack for different cryptocurrencies?
#2Can someone ELI5 how these numbers fit together? It costs me $3/hr to 51% DeepOnion, which has a market cap of $1.95M. In practical terms, what does that mean?
Re: Cost of a 51% attack for different cryptocurrencies?
#3$705k per hour for Bitcoin - these numbers sound very expensive.
Do they take into account that during an attack the attacker will earn block rewards and transaction fees?
Because if not, then they vastly overestimate the costs.
This sounds like it is based on the some energy price that would be needed to do 51% of Bitcoins hashing.
Doing so could very well be profitable.
The reason it would be hard to do is that the attacker would have to gather a ton of hardware that way way exceeds the energy costs.
Re: Cost of a 51% attack for different cryptocurrencies?
#4Since it took a while for me to understand this. A 51% attack doesn’t let you steal money from anyone. It essentially lets you block all transactions from making it to the blockchain. Nodes will still verify all transactions and ignore transactions that are invalid.
Edit: you can also create multiple forks and switch between them. External viewers will see both forks and if they don’t or can’t handle the difference they could experience a double spend.
That being said any miner has the ability to sort transaction any way they want which can give them an advantage. So if someone has a lot of hashing power they can use that ability to delay certain transactions or to give preference to others.
Re: Cost of a 51% attack for different cryptocurrencies?
#51) If a big crypto-community notices an attack, the cost of a 51% attack would rise
2) There are mechanisms to offer smaller cryptocurrencies Bitcoin level security, like Komodo's Delayed Proof of Work (https://komodoplatform.com/security-delayed-proof-of-work-dp...)
Re: Cost of a 51% attack for different cryptocurrencies?
#6QuarkChain QKC $6.01 M Ethash 10 GH/s $7 69,816%
So 7$ is the nicehash cost? But isn't nicehash an out of the box solution? So if I wanted to actually execute a 51% attack I'd have to deploy my own malicious mining software to the nodes, that then issued an invalid transaction and forced consensus on it ... is that the idea? Can someone who knows a little bit more about this fill me in?
Re: Cost of a 51% attack for different cryptocurrencies?
#7$705k per hour for Bitcoin - these numbers sound very expensive. Do they take into account that during an attack the attacker will earn block rewards and transaction fees? Because if not, then they vastly overestimate the costs. This sounds like it is based on the some energy price that would be needed to do 51% of Bitcoins hashing. Doing so could very well be profitable. The reason it would be hard to do is that the…
Only of those blocks are accepted by the chain in the future. Zero transaction blocks or blocks with invalid transactions could easily be ignore by the next miner.
Re: Cost of a 51% attack for different cryptocurrencies?
#8Since it took a while for me to understand this. A 51% attack doesn’t let you steal money from anyone. It essentially lets you block all transactions from making it to the blockchain. Nodes will still verify all transactions and ignore transactions that are invalid. Edit: you can also create multiple forks and switch between them. External viewers will see both forks and if they don’t or can’t handle the difference t…
Or they can double spend some crypto, that is generally the main goal here
Re: Cost of a 51% attack for different cryptocurrencies?
#9Since it took a while for me to understand this. A 51% attack doesn’t let you steal money from anyone. It essentially lets you block all transactions from making it to the blockchain. Nodes will still verify all transactions and ignore transactions that are invalid. Edit: you can also create multiple forks and switch between them. External viewers will see both forks and if they don’t or can’t handle the difference t…
If you can hash faster than everyone else combined you can re-write history. So you could make a transaction and then re-write that transaction out of history allowing you to spend that money again.
When you make a valid transaction, you have the necessary details for both that valid transaction and no transaction at all. Just because you can't make invalid transactions doesn't mean you can't effectively steal.
This is why lightning network is a shitshow, because you have to be constantly alert for that behaviour.
Re: Cost of a 51% attack for different cryptocurrencies?
#10$705k per hour for Bitcoin - these numbers sound very expensive. Do they take into account that during an attack the attacker will earn block rewards and transaction fees? Because if not, then they vastly overestimate the costs. This sounds like it is based on the some energy price that would be needed to do 51% of Bitcoins hashing. Doing so could very well be profitable. The reason it would be hard to do is that the…
Only of those blocks are accepted by the chain in the future. Zero transaction blocks or blocks with invalid transactions could easily be ignore by the next miner.
Well, the reason for an attack is to reverse transactions. For that to have any value, the blocks must be accepted by the chain in the future.
And no, a miner can not "easily" ignore previous blocks.
And blocks with invalid transactions get ignored by everyone anyhow.