基于多级网络编码的多副本云数据存储

云数据存储的快速发展对数据的可用性提出了较高要求.目前,主要采用纠删码计算数据编码块进行分布式冗余数据存储来保证数据的可用性.虽然这种数据编码技术保证了存储数据的安全性并减少了额外的存储空间,但在损坏数据恢复时会产生较大的计算和通信开销提出一种基于多级网络编码的多副本生成和损坏数据恢复算法算法基于多级网络编码对纠删码的...

Multi-Replica Cloud Data Storage Based on Hierarchical Network Coding

The rapid development of cloud data storage presents a high demand on the availability of stored data.Currently,the main technique of ensuring data availability is to use erasure coding to calculate coded blocks for the stored data,and then utilize distributed storage to store multiple redundant coded blocks in cloud storage space.Although this data coding technology can ensure the security of stored data and reduce extra storage space,it also causes a large calculation and communication overhead when recovering corrupted data.In this paper a multi-replica generation and corrupted data recovery algorithm is proposed based on hierarchical network coding.The algorithm improves the coding matrix of erasure coding based on hierarchical network coding to form the hierarchical coding(HC).Then multi-replicas which are built based on the cascade of the hierarchical coding forms the coding relationship between each other.In the process of corrupted data recovery,the data encoding information provided by the data owner and the complete data blocks stored by the cloud server are jointly computed to recover the corrupted data blocks,avoiding remote data downloading from the cloud storage space.Theoretical analysis and simulation experiments indicate that the proposed algorithm reduces the communication overhead significantly when recovering corrupted data and improves the availability of stored data under the same storage space.