Understanding 51% Attacks in Blockchain Networks
A 51% attack occurs when a single network miner or group of miners controls more than half of a blockchain network’s hash rate. This gives the attacker the power to manipulate transactions, alter transaction sequences, and potentially revert past transactions through double spending.
Study Shows Attacking Bitcoin and Ethereum Is Not Worth It
A recent study suggests that executing 51% attacks on Bitcoin and Ethereum is financially unviable due to their current security setups. CoinMetrics’ calculations reveal that an attacker would need around $34.39 billion to carry out a 34% attack on the Ethereum network. The assault would take several months to breach the threshold and gain control over the network.
Attacking Bitcoin would also be cost-prohibitive, with production expenses estimated at over $20 billion. Even using the most powerful ASIC available, it would still cost around $5.6 billion by December 2023.
The study concludes that the security measures of Bitcoin and Ethereum have reached a level where the costs and dangers associated with 51% attacks outweigh the potential benefits.
Other Blockchains Remain Vulnerable
While Bitcoin and Ethereum have robust security measures, many other networks are not as secure. Blockchain networks like Bitcoin SV, Firo (formerly Zcoin), and Ethereum Classic have experienced instances of 51% attacks in recent times. These attacks highlight the ongoing risks faced by lesser-known blockchains.