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arXiv · 1702.02642

On minimum distance of locally repairable codes

Mehrtash Mehrabi·Massoud Ardakani
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Abstract

Distributed and cloud storage systems are used to reliably store large-scale data. Erasure codes have been recently proposed and used in real-world distributed and cloud storage systems such as Google File System, Microsoft Azure Storage, and Facebook HDFS-RAID, to enhance the reliability. In order to decrease the repair bandwidth and disk I/O, a class of erasure codes called locally repairable codes (LRCs) have been proposed which have small locality compare to other erasure codes. Although LRCs have small locality, they have lower minimum distance compare to the Singleton bound. Hence, seeking the largest possible minimum distance for LRCs have been the topic of many recent studies. In this paper, we study the largest possible minimum distance of a class of LRCs and evaluate them in terms of achievability. Furthermore, we compare our results with the existence bounds in the literature.

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Mehrtash Mehrabi, Massoud Ardakani. 2017-02-08. On minimum distance of locally repairable codes. https://doi.org/10.1109/cwit.2017.7994819

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