关键词: 区块链, 去中心化, 分布式存储, 元数据

Abstract: In the distributed storage systems, the metadata stored on the central node, which is prone to a single point of failure and is easily modified by malicious ones. Although the problem can be avoided to some extent by using backup nodes, the synchronization and handover between the nodes are less efficient. At the same time, nodes that store metadata can agree on modifying metadata, which is lacking credibility. For the problems of distributed storage system, a decentralized data storage model is proposed, namely DMB（Decentralized Metadata Blockchain）, which combines with the characteristics of blockchain. The DMB model guarantees metadata integrity by saving metadata in blocks, redundant storage for blockchain, and collaboration validation. The model is divided into two phases which are storage phase and verification phase. In the storage phase, the model sends the user’s signature and locations of data to verification nodes, and uses the signature and data locations to generate metadata block. In the verification phase, the verification nodes check whether the local and global states of the metadata block chain are the same. If they are not the same, the DMB model performs the synchronization of the state, and then the verification nodes retrieve local the metadata blockchain to verify the integrity of metadata. The theoretical and experimental results show that the DMB model can guarantee the retrievability and possession of the metadata, and has better concurrent processing ability, which has little effect on the efficiency of the data stored.

Key words: blockchain, decentration, distributed storage, metadata