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arXiv · 1701.04120

Optimal Repair Schemes for Some Families of Full-Length Reed-Solomon Codes

Hoang Dau·Olgica Milenkovic
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Abstract

Reed-Solomon codes have found many applications in practical storage systems, but were until recently considered unsuitable for distributed storage applications due to the widely-held belief that they have poor repair bandwidth. The work of Guruswami and Wootters (STOC'16) has shown that one can actually perform bandwidth-efficient linear repair with Reed-Solomon codes: When the codes are over the field $\mathbb{F}_{q^t}$ and the number of parities $r \geq q^s$, where $(t-s)$ divides $t$, there exists a linear scheme that achieves a repair bandwidth of $(n-1)(t-s)\log_2 q$ bits. We extend this result by showing the existence of such a linear repair scheme for every $1 \leq s < t$. Moreover, our new schemes are optimal among all linear repair schemes for Reed-Solomon codes when $n = q^t$ and $r = q^s$. Additionally, we improve the lower bound on the repair bandwidth for Reed-Solomon codes, also established in the work of Guruswami and Wootters.

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Hoang Dau, Olgica Milenkovic. 2017-01-15. Optimal Repair Schemes for Some Families of Full-Length Reed-Solomon Codes. https://arxiv.org/abs/1701.04120

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