Rethinking Fractional Repetition Codes: New Construction and Code Distance

摘要

Modern storage systems are increasingly employing erasure codes to protect data against disk failures. Various codes have been elaborately constructed to achieve the desirable storage performance. In this letter, we consider fractional repetition (FR) codes, which provide uncoded exact repairs with minimum repair bandwidth. We present a novel code construction framework that is built on existing codes to generate new FR codes. The proposed framework extends the construction of FR codes to a larger set of parameters, and is applicable to heterogeneous storage networks. Moreover, we characterize a general expression for the minimum distance of FR codes, which is derived from a simple analysis and depends on the size of stored file. We further present closed-form expressions on the minimum distance for some special scenarios.