Towards Building Post-Quantum Secure Ethereum

Public blockchains, such as Ethereum and Bitcoin, use the Elliptic Curve Digital Signature Algorithm (ECDSA), specifically Secp256k1, to enable users to authenticate transactions. However, this cryptographic system is relatively vulnerable to quantum attacks, which may become truly feasible in the next few years through quantum computing advances. Existing studies recognize the importance of post-quantum secure signatures, but the actual implementation and transition of post-quantum secure blockchains still require further investigation.In this work, we leverage pk-FALCON512, a lattice-based and post-quantum secure signature scheme, to replace Secp256k1 in the Ethereum execution client. We analyze the performance and storage implications of this replacement. Our evaluation results show that pk-FALCON512 is approximately 23,000× , 28× 3× slower, and times than Secp256k1 in key generation, signature generation, and signature verification, respectively. Specifically, signature verification, critical for on-chain operations, increases from 24µs to 74µs, and this indicates an acceptable trade-off for adopting post-quantum secure signatures. In terms of storage, pk-FALCON512 needs 15× more space with cryptographic elements, which might increase the average block size by approximately 3.85×. These results show feasibility in practice for integrating post-quantum cryptography schemes into Ethereum for further research.