The proliferation of resource-constrained devices has become prevalent across various digital applications, including smart homes, healthcare, the Internet of Vehicles, and the Internet of Flying Things, among others. However, the integration of these devices brings many security issues. To address these concerns, Blockchain technology has been widely adopted due to its robust security characteristics, including immutability, cryptography, and distributed consensus. However, implementing the blockchain within these networks is highly challenging due to the limited resources of the employed devices and the resource-intensive requirements of the blockchain. To overcome these challenges, a multitude of researchers have proposed lightweight blockchain solutions specifically designed for resource-constrained networks. In this paper, we present a taxonomy of lightweight blockchain solutions proposed in the literature. More precisely, we identify five areas within the "lightweight" concept, namely, blockchain architecture, device authentication, cryptography model, consensus algorithm, and storage method. We discuss the various methods employed in each "lightweight" category, highlighting existing gaps and identifying areas for improvement. Our review highlights the missing points in existing systems and paves the way to building a complete lightweight blockchain solution for networks of resource-constrained devices.

翻译：随着资源受限设备在智能家居、医疗健康、车联网及飞行物联网等众多数字应用中的广泛普及，其集成过程带来了诸多安全问题。为应对这些挑战，区块链技术凭借其不可篡改、密码学机制及分布式共识等强大安全特性被广泛应用。然而，由于设备资源有限且区块链本身对资源需求较高，在这些网络中部署区块链面临巨大困难。针对上述难题，大量研究者提出了专为资源受限网络设计的轻量级区块链解决方案。本文对现有文献中的轻量级区块链解决方案进行了分类梳理，具体从轻量级概念的五个维度展开：区块链架构、设备认证、密码学模型、共识算法及存储方法。我们深入探讨了每个轻量级类别中的不同实现方法，揭示了现有空白领域并确定了改进方向。本综述聚焦于现有系统的缺失环节，为构建面向资源受限设备网络的完整轻量级区块链解决方案奠定基础。