As quantum computing advances toward practical deployment, it threatens a wide range of classical cryptographic mechanisms, including digital signatures, key exchange protocols, public-key encryption, and certain hash-based constructions that underpin modern network infrastructures. These primitives form the security backbone of most blockchain platforms, raising serious concerns about the long-term viability of blockchain systems in a post-quantum world. Although migrating to post-quantum cryptography may appear straightforward, the substantially larger key sizes and higher computational costs of post-quantum primitives can introduce significant challenges and, in some cases, render such transitions impractical for blockchain environments. In this paper, we examine the implications of adopting post-quantum cryptography in blockchain systems across four key dimensions. We begin by identifying the cryptographic primitives within blockchain architectures that are most vulnerable to quantum attacks, particularly those used in consensus mechanisms, identity management, and transaction validation. We then survey proposed post-quantum adaptations across existing blockchain designs, analyzing their feasibility within decentralized and resource-constrained settings. Building on this analysis, we evaluate how replacing classical primitives with post-quantum alternatives affects system performance, protocol dynamics, and the incentive and trust structures that sustain blockchain ecosystems. Our study demonstrates that integrating post-quantum signature schemes into blockchain systems is not a simple drop-in replacement; instead, it requires careful architectural redesign, as naive substitutions risk undermining both security guarantees and operational efficiency.

翻译：随着量子计算向实际部署迈进，其威胁着包括数字签名、密钥交换协议、公钥加密以及支撑现代网络基础设施的某些基于哈希的构造在内的广泛经典密码学机制。这些原语构成了大多数区块链平台的安全支柱，引发了关于区块链系统在后量子世界中长期可行性的严重关切。尽管迁移至后量子密码学看似直接，但后量子原语显著更大的密钥尺寸和更高的计算成本可能带来重大挑战，在某些情况下甚至使得此类过渡在区块链环境中不可行。本文从四个关键维度考察了在区块链系统中采用后量子密码学的影响。我们首先识别区块链架构中最易受量子攻击的密码学原语，特别是用于共识机制、身份管理和交易验证的那些。随后，我们综述了现有区块链设计中提出的后量子适应性方案，分析其在去中心化和资源受限环境中的可行性。基于此分析，我们评估了用后量子替代方案替换经典原语如何影响系统性能、协议动态以及维持区块链生态系统的激励与信任结构。我们的研究表明，将后量子签名方案集成到区块链系统中并非简单的即插即用替换；相反，它需要谨慎的架构重新设计，因为简单的替换可能同时破坏安全保证和运行效率。