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arXiv · 2302.09325

MDS Array Codes With (Near) Optimal Repair Bandwidth for All Admissible Repair Degrees

Jie Li·Yi Liu·Xiaohu Tang·Yunghsiang S. Han·Bo Bai·Gong Zhang
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Abstract

Abundant high-rate (n, k) minimum storage regenerating (MSR) codes have been reported in the literature. However, most of them require contacting all the surviving nodes during a node repair process, resulting in a repair degree of d=n-1. In practical systems, it may not always be feasible to connect and download data from all surviving nodes, as some nodes may be unavailable. Therefore, there is a need for MSR code constructions with a repair degree of d k, and has a smaller sub-packetization level or finite field than some existing constructions. Additionally, in conjunction with a previous generic transformation to reduce the sub-packetization level, we obtain an MDS array code with a small sub-packetization level and $(1+\epsilon)$-optimal repair bandwidth (i.e., $(1+\epsilon)$ times the optimal repair bandwidth) for repair degree d=n-1. This code outperforms some existing ones in terms of either the sub-packetization level or the field size.

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Jie Li, Yi Liu, Xiaohu Tang, Yunghsiang S. Han, Bo Bai, Gong Zhang. 2023-02-18. MDS Array Codes With (Near) Optimal Repair Bandwidth for All Admissible Repair Degrees. https://arxiv.org/abs/2302.09325

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