In this paper, we introduce a model of a single-failure locally recoverable
distributed storage system. This model appears to give rise to a problem
seemingly dual of the well-studied index coding problem. The relation between
the dimensions of an optimal index code and optimal distributed storage code of
our model has been established in this paper. We also show some extensions to
vector codes.Comment: A small new section and new references added. A minor error corrected
from the previous versio