Ethereum co-founder Vitalik Buterin on Thursday outlined a roadmap to protect the blockchain from the long-term risks of quantum computing — a move that comes shortly after the Ethereum Foundation established a dedicated post-quantum research team to study the issue.
Although practical quantum computers capable of breaking modern cryptography do not yet exist, they may one day crack the digital signatures and cryptographic systems that secure Ethereum.
In a post on X, Buterin identified four key areas of vulnerability: validator signatures used in consensus, Ethereum’s data availability system, daily wallet signatures, and certain zero-knowledge proofs used by applications and layer-2 networks.
A big part of the plan involves changing how Ethereum’s validators sign and verify blocks. Right now they use a type of digital signature called BLS. In a world of powerful quantum computers, these signatures could eventually be broken. Buterin suggests switching to “hash-based” signatures, which are considered much more secure against quantum attacks.
Another area that needs to be updated is how Ethereum controls and stores large batches of transaction data. The system it uses today relies on a cryptographic tool called KZG commitments. Replacing it with a quantum-safe alternative is possible, Buterin said, but it would require significant behind-the-scenes engineering and could make some parts of the system more complicated.
For regular users, the proposed fix is a planned upgrade called EIP-8141. Simply put, this upgrade would make Ethereum wallets more flexible. Today, most wallets rely on one standard type of digital signature to authorize transactions. EIP-8141 will enable accounts to switch to different types of signatures in the future – including those designed to be secure against quantum computers.
There is a similar problem with zero-knowledge proofs, a type of advanced cryptography used by data protection tools and many layer-2 scaling networks. Quantum-safe versions of these proofs are currently far more expensive to verify on Ethereum.
Buterin pointed to a long-term solution built into EIP-8141 known as “validation frameworks.” These would allow the network to collect many signatures and proofs and replace them with a single combined proof. Instead of verifying each one individually on the blockchain, Ethereum would only need to verify a compressed proof, which helps keep costs down.
Read more: The quantum threat becomes real: Ethereum Foundation prioritizes security with leanVM and PQ signatures
