Vitalik Buterin pushes for Ethereum to respond to 51% attacks in a more automated way

Ethereum ETH +1.02% co-founder Vitalik Buterin is advocating for the Ethereum network to be more prepared for the hypothetical case of censorship under a 51% attack.

“This is the thing I’m advocating we do more research on and we build,” he said in a keynote speech at ETHCC in Brussels.

Buterin was considering the notion of a 51% attack, a state where more Ethereum blocks are being produced by a malicious actor (or multiple working in coordination) than by honest actors. He argued that one of the biggest concerns is that this could result in censorship on the network.

A potential response to such an attack, he said, would be for honest validators to move to a fork of the chain. The current plan would largely rely on social consensus, with community members working together to agree on a fork.

However, Buterin argued that it would be better if the network was more prepared for such a response. He said that it would be good for this response to be largely automated and planned out in advance.

"We want to make the response to 51% attacks be something that is as automated as possible. So if you are a validator then your node should run software, which, if it detects transactions are being censored – or some validators are being censored or it's being censored – it will automatically counter-censor the majority chain and all honest nodes will just automatically, as a result of code that they’re running, coordinate on the same minority software," he said.

Buterin acknowledged that it would be impossible to get 100% of the network to automatically move to a fork as there are a lot of limitations. But he said: “The closer you can get to this, then the more we get to a situation where the amount of effort that social consensus needs to do is much lower.”

He said the technological layer at the very least needs to present one obvious winning candidate for a soft fork that the community can rally around if it needs to move away from a censoring chain.

Buterin's other suggestions for Ethereum

Buterin also argued for increased adoption of light clients across Ethereum's infrastructure layer, particularly including wallets. He said they should also support the verification of zk-EVMs, providing further support for Layer 2 networks.

He also addressed the issue of quantum resistance. He noted that this is a pending concern for the Ethereum blockchain. However, he argued that the network has four elements that are at risk – Merkle trees, consensus signatures, blobs and user accounts – but that each have their own solutions.

Beyond this, he pushed for further protocol simplification to make things easier for developers and users.