Quote from: sp_ on June 19, 2022, 01:20:01 PM

Quote from: bitquad on June 19, 2022, 08:57:55 AM

Ethereum has over 300,000 validators on the Beacon Chain. 3 mining pools can theoretically execute a 51% attack on POW Ethereum. And 4 mining pools can theoretically implement a 51% attack o Bitcoin. Sounds like the validators might be more decentralized?

Network    Validator Count   % of Supply Staked
Cardano (ADA)    2,977   69.60% of 33 billion circulating supply
Avalanche (AVAX)    1,199   49.38% of 246 million circulating supply
Ethereum Beacon Chain   309,169   8.2% of 119 million circulating supply

300000 validators, but if one validator or a group of validators control 8.3% they can theoretically execute a 51% attack. with only 8.3% of the network. An attack on ethereum will not only affect Ethereum, but also all the other coins that base their security on the ethereum. Coins like Tether (68BUSD) , Usd coin (55BUSD) and other stablecoins.

How can you do a 51% attack with 8.3%. That makes no sense at all. You need 51% to make a 51% attack. What's your source for that 8.3% claim?

https://ethereum.org/en/developers/docs/consensus-mechanisms/pos/#:~:text=in%20its%20history.-,Proof%2Dof%2Dstake%20and%20security,ETH%20(about%20%2415%2C000%2C000%2C000%20USD).

PROOF-OF-STAKE AND SECURITY
The threat of a 51% attack still exists on proof-of-stake as it does on proof-of-work, but it's even riskier for the attackers. A attacker would need 51% of the staked ETH (about $15,000,000,000 USD). They could then use their own attestations to ensure their preferred fork was the one with the most accumulated attestations. The 'weight' of accumulated attestations is what consensus clients use to determine the correct chain, so this attacker would be able to make their fork the canonical one. However, a strength of proof-of-stake over proof-of-work is that the community has flexibility in mounting a counter-attack. For example, the honest validators could decide to keep building on the minority chain and ignore the attacker's fork while encouraging apps, exchanges, and pools to do the same. They could also decide to forcibly remove the attacker from the network and destroy their staked ether. These are strong economic defenses against a 51% attack.

51% attacks are just one flavor of malicious activity. Bad actors could attempt long-range attacks (although the finality gadget neutralizes this attack vector), short range 'reorgs' (although proposer boosting and attestation deadlines mitigate this), bouncing and balancing attacks (also mitigated by proposer boosting, and these attacks have anyway only been demonstrated under idealized network conditions) or avalanche attacks (neutralized by the fork choice algorithms rule of only considering the latest message).

Overall, proof-of-stake, as it is implemented on Ethereum, has been demonstrated to be more economically secure than proof-of-work.

PROS AND CONS