Abstract: Blockchain stores transaction data in the form of distributed ledger, and its nodes hold copies of current data by storing hash chain. Due to the particularity of the blockchain structure, the number of blocks increases over time and the storage pressure of nodes also increases with the increasing of blocks, so that the storage scalability has become one of the bottlenecks in blockchain development. To address this problem, a blockchain storage expansion model based on Chinese Remainder Theorem (CRT) was proposed. In the model, the blockchain was divided into high-security blocks and low-security blocks, which were stored by different storage strategies. Among them, low-security blocks were stored in the form of network-wide preservation (all nodes need to preserve the data), while the high-security blocks were stored in a distributed form after being sliced by the CRT-based partitioning algorithm. In addition, the error detection and correction of Redundant Residual Number System (RRNS) was used to restore data to prevent malicious node attacking, so as to improve the stability and integrity of data. Experimental results and security analysis show that the proposed model not only has security and fault tolerance ability, but also ensures the integrity of data, as well as effectively reduces the storage consumption of nodes and increases the storage scalability of the blockchain system.

Key words: blockchain, storage scalability, Chinese Remainder Theorem (CRT), distributed storage, Redundant Residual Number System (RNNS), data integrity

摘要： 区块链以分布式账本的形式存储交易数据，其节点通过存储哈希链来持有当前数据的副本。由于区块链链式结构的特殊性，区块的数量会随着时间推移不断增加，节点承受的存储压力也随之增大，因此存储扩展性成为区块链发展的瓶颈之一。针对该问题，提出了一种基于中国剩余定理（CRT）的区块链存储扩展模型。模型将区块链分为高安全性区块和低安全性区块，并对它们采取不同的存储策略。其中，低安全性区块以全网保存（所有节点都需保存）的形式进行存储，高安全性区块被基于CRT的分割算法分片后以分布式的形式进行存储。此外，利用冗余余数系统（RRNS）的错误检测与纠正来防止恶意节点攻击，进而提高数据稳定性和完整性。实验结果与安全性分析表明，所提模型在具有安全性、容错性的同时保障了数据的完整性，还能有效地减少节点的存储消耗，增强区块链系统的存储扩展性。

关键词: 区块链, 存储扩展性, 中国剩余定理, 分布式存储, 冗余余数系统, 数据完整性