A Cooperative Repair Scheme for Zigzag MSR Codes in Distributed Storage Systems
Yajuan Liu, Han Cai, Xiaohu Tang
TL;DR
This work addresses the challenge of efficiently repairing multiple failed nodes in Zigzag MSR codes by introducing a cooperative repair scheme that attains the optimal bandwidth $\ abla = \frac{h(n-1)N}{d-k+h}$ for any $h$ failures. The authors employ a space-sharing construction with $d-k+h$ instances and a four-step process—Summing, Grouping, Downloading, and Cooperation—tied together by a carefully designed recover matrix $R$ whose invertibility ensures solvability of the repair equations. Key contributions include achieving optimal cooperative repair for Zigzag MSR codes with sub-packetization $N=(d-k+h)s^n$ and field size $q \ge n+1$, significantly reducing the finite-field requirement compared to prior schemes. The results advance practical multi-node repair in distributed storage by lowering resource demands while preserving the MDS and optimal repair properties of Zigzag MSR codes.
Abstract
In this paper, we propose a novel cooperative repair scheme for Zigzag MSR codes with optimal repair bandwidth, enabling the repair of any h failed nodes. To the best of our knowledge, this is the first optimal cooperative repair scheme for Zigzag MSR codes. Compared to previous cooperative repair schemes for MSR codes, our scheme significantly reduces the size of the finite field to Fq,q>=n+1.