A Performance Comparison of Traditional and Post-Quantum Cryptographic Algorithms for Blockchain Applications

Abstract

Under the pressure of the increasing threat of quantum computing to classical cryptographic foundations, it is urgent to transition from the traditional Elliptic Curve Digital Signature Algorithm (ECDSA) to Post-Quantum Cryptography (PQC). This study extracts the public key size, signature size, key pair generation time, signing time, and verification time of ECDSA and three PQC schemes—Module-Lattice-Based Digital Signature Algorithm (ML-DSA), SPHINCS+, and Falcon-based Digital Signature Algorithm (FN-DSA)—from the referenced datasets to provide a comprehensive comparative analysis. Three evaluation metrics are used to assess the impact of the PQC schemes on blockchain performance: transaction size expansion ratio, throughput impact factor, and block payload cost increment. The results show that FN-DSA reaches a transaction size expansion ratio of 12.33 at Level 5 and a throughput impact factor of 0.218 at Level 5. The lowest block payload cost increment reported for FN-DSA is 0.3879 at Level 1. These results indicate that FN-DSA performs particularly well in the size-related metrics, while ML-DSA demonstrates the strongest time performance among the evaluated PQC schemes. All PQC schemes produce larger transaction sizes than ECDSA, whereas ML-DSA and FN-DSA demonstrate comparable or better time performance. Sphincs+ provides strong quantum resistance but introduces substantial computational and storage overhead. These findings provide insights into the selection of appropriate PQC schemes for quantum-resilient blockchain environments.