摘要
存储系统中的纠删码用在整个磁盘被擦除的错误模式下恢复丢失的数据.但在实际应用中,磁盘和扇区同时被擦除的情况更易发生.针对这种更一般的错误模式,Blaum等学者提出了SD码和PMDS码.相较应用于RAID存储架构中的纠删码,在磁盘和扇区同时被擦除的错误模式下,SD码和PMDS码能够节省更多的存储空间.设计具有良好容错能力的SD码和PMDS码是一个公开问题.对SD码和PMDS码的构造主要基于校验矩阵或生成矩阵,但局部校验数m和全局校验数s均有限制.在已知的基于校验矩阵构造的SD码和PMDS码中,当全局校验个数s=3或4时,局部校验个数m满足m≤2;当局部校验个数m≥1时,全局校验个数s满足s≤2.在本文中,我们给出具有更高容错能力的SD码和PMDS码,参数满足m≥1且s=3.在已知的基于生成矩阵构造的SD码中,参数满足m≥1且s=3.在本文中,我们给出参数满足m≥1且s=4的SD码.
Erasure codes used in storage systems are designed to tolerate the failures of entire disks.However, the most common type of failures is the mode of disk failures accompanied by sector failures.Blaum et al. proposed SD codes and PMDS codes for this kind of general failures. SD codes and PMDS codes consume far less storage resources than traditional erasure codes used in RAID storage structure. It has been an open problem for some years to construct SD codes and PMDS codes with good fault tolerance capability. The constructions of SD codes and PMDS codes are mainly based on parity check matrices or generator matrices. However, the local parity number m and the global parity number s are limited. In known constructions of SD codes and PMDS codes based on parity check matrices, if the global parity number s = 3 or 4, the local parity number m has to satisfy m≤2; if the local parity number m≥1, the global parity number s has to satisfy s≤2. In this paper, we present a new construction of SD codes and PMDS codes based on parity check matrices with m≥1 and s = 3, which means better fault tolerance capability. For SD codes, so far the best construction based on generator matrices has parameters up to m≥1 and s = 3. In this paper, we present a new construction of SD codes with m≥1 and s = 4.
作者
荣幸
杨小龙
胡红钢
RONG Xing, YANG Xiao-Long, HU Hong-Gang(CAS Key Laboratory of Electromagnetic Space Information, University of Science and Technology of China Hefei 230027, Chin)
出处
《密码学报》
CSCD
2018年第2期151-166,共16页
Journal of Cryptologic Research
基金
国家自然科学基金项目(61522210
61632013)~~
