In this paper, we propose locally repairable codes (LRCs) with optimal
minimum distance for distributed storage systems (DSS). A two-layer encoding
structure is employed to ensure data reconstruction and the designated repair
locality. The data is first encoded in the first layer by any existing maximum
distance separable (MDS) codes, and then the encoded symbols are divided into
non-overlapping groups and encoded by an MDS array code in the second layer.
The encoding in the second layer provides enough redundancy for local repair,
while the overall code performs recovery of the data based on redundancy from
both layers. Our codes can be constructed over a finite field with size growing
linearly with the total number of nodes in the DSS, and facilitate efficient
degraded reads.Comment: This paper has been withdrawn by the author due to inaccuracy of
Claim