PQ-DPoL: An Efficient Post-Quantum Blockchain Consensus Algorithm

The advancement of quantum computers and the potential polynomial-time solution of Elliptic Curve Cryptography (ECC) using the Shor algorithm pose a significant threat to blockchain security. This paper presents an efficient quantum-secure blockchain with our novel consensus algorithm. We integrate a post-quantum signature scheme into the transaction signing and verification process of our blockchain, ensuring its resistance against quantum attacks. Concretely, we adopt the Dilithium signature scheme, which is one of the selected algorithms in the NIST Post-Quantum Cryptography (PQC) standardization. Not surprisingly, the incorporation of a post-quantum signature scheme leads to a reduction in the number of Transactions Per Second (TPS) processed by our blockchain. To mitigate this performance degradation, we introduce a new consensus algorithm that effectively combines the Proof of Luck (PoL) mechanism with a delegated approach. We strive to build an efficient and secure blockchain for the post-quantum era by benchmarking our blockchain, adjusting the security parameters of Dilithium, and refining the components of the consensus algorithm.