Research on Decentralized Storage Based on a Blockchain

Abstract

The current distributed storage solutions are still concentrated in third-party storage service providers, and the stored data are concentrated in a few cloud servers, which inevitably brings the risk of data loss, leakage, and tampering, so it is imperative to study a distributed storage and decentralized storage system. How to maintain the consistency of data in a distributed environment has become a problem in building decentralized applications, until the emergence of blockchain technology, whose decentralized, non-tamperable, and traceable features can solve this problem well. In this paper, we design a decentralized storage system combining Hyperledger Fabric and Inter Planetary File System (IPFS). In addition, from the perspective of security and availability of the decentralized storage system, we study the partitioning and the k-r allocation scheme of the stored data, propose the allocation function about the stored files, derive the mathematical formula of file security and availability based on the allocation function, and discuss the optimal parameter setting of the allocation function based on the formula to guarantee the high security and availability of the stored files. The experimental results show that the performance of the k-r allocation policy based on the minimum number nodes (MNN) is better than that of the k-r allocation policy based on the minimum slices number (MSN); however, with the same security and availability guarantees, the MNN policy will have more copies relative to the MSN policy, which is relatively wasteful of space.