Rack-Aware MSR Codes with Multiple Erasure Tolerance

Jiaojiao Wang; Dabin Zheng; Shenghua Li

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arXiv · 2109.08302

Rack-Aware MSR Codes with Multiple Erasure Tolerance

Jiaojiao Wang·Dabin Zheng·Shenghua Li

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Abstract

The minimum storage rack-aware regenerating (MSRR) code is a variation of regenerating codes that achieves the optimal repair bandwidth for a single node failure in the rack-aware model. The authors in~\cite{Chen-Barg2019} and~\cite{Zhou-Zhang2021} provided explicit constructions of MSRR codes for all parameters to repair a single failed node. This paper generalizes the results in~\cite{Chen-Barg2019} to the case of multiple node failures. We propose a class of MDS array codes and scalar Reed-Solomon (RS) codes, and show that these codes have optimal repair bandwidth and error resilient capability for multiple node failures in the rack-aware storage model. Besides, our codes keep the same access level as the low-access constructions in~\cite{Chen-Barg2019} and~\cite{Zhou-Zhang2021}.

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Jiaojiao Wang, Dabin Zheng, Shenghua Li. 2021-09-17. Rack-Aware MSR Codes with Multiple Erasure Tolerance. https://arxiv.org/abs/2109.08302

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