Quantum Blockchain Survey: Foundations, Trends, and Gaps
Saurav Ghosh, Niloy Deb Roy Mishu
TL;DR
The paper investigates how quantum computing challenges classical blockchains and surveys two main responses: post-quantum blockchains that harden classical primitives and quantum blockchains that embed quantum mechanisms such as entanglement and QKD. It analyzes cryptographic foundations, network architectures, and implementation challenges, mapping open problems across hardware, routing, and consensus. A core contribution is the comparative framing of post-quantum versus quantum approaches, highlighting deployment readiness versus theoretical security guarantees. The work advocates phased adoption, prototyping, and hybrid architectures to advance secure decentralized systems in the quantum era.
Abstract
Quantum computing poses fundamental risks to classical blockchain systems by undermining widely used cryptographic primitives. In response, two major research directions have emerged: post-quantum blockchains, which integrate quantum-resistant algorithms, and quantum blockchains, which leverage quantum properties such as entanglement and quantum key distribution. This survey reviews key developments in both areas, analyzing their cryptographic foundations, architectural designs, and implementation challenges. This work provides a comparative overview of technical proposals, highlight trade-offs in security, scalability, and deployment, and identify open research problems across hardware, consensus, and network design. The goal is to offer a structured and comprehensive reference for advancing secure blockchain systems in the quantum era.