Post-Quantum Blockchain Multi-Party Transaction Scheme Based on Double Signatures

Abstract

To address the threat posed by quantum computing to the widely used ECDSA in current blockchain systems, this paper proposes a post-quantum multi-party transaction scheme based on a dual-signature mechanism combining threshold ECDSA and ML-DSA. The scheme utilizes threshold ECDSA to ensure ecosystem compatibility while leveraging ML-DSA to provide long-term quantum resistance, with transaction organization optimized via a Merkle tree structure. Security analysis confirms that the scheme achieves decentralization, post-quantum security, and unforgeability. Experimental results show that the system achieves a signature throughput of 1,200 TPS with a verification latency below 50 ms. Key generation latency reaches up to 678.78 μs as the number of participants increases, and signature latency is approximately 109 ms under a batch size of 200 transactions. The scheme is well-suited for high-value scenarios such as cross-border payments and digital asset trading.