Threats and Opportunities: Blockchain Meets Quantum Computation

TL;DR

This paper analyzes the vulnerabilities of blockchain technology in the face of quantum computing advancements and proposes quantum-based solutions to enhance its security and efficiency.

Contribution

It identifies specific quantum threats to blockchain and introduces quantum security methods like QKD and quantum consensus protocols as novel solutions.

Findings

Quantum threats can compromise blockchain security

Quantum key distribution enhances blockchain security

Quantum protocols enable faster consensus

Abstract

This article considered deficiencies of the flourishing blockchain technology manifested by the development of quantum computation. We show that the future blockchain technology would under constant threats from the following aspects: 1) Speed up the generation of nonces; 2) Faster searching for hash collisions; 3) Break the security of the classical encryption. We also demonstrate that incorporating some quantum properties into blockchain makes it more robust and more efficient. For example people can establish a quantum-security blockchain system that utilizes quantum key distribution (QKD), and quantum synchronization and detectable Byzantine agreement (DBA) can help the blockchain systems achieve faster consensus even if there exist a number of malicious nodes.