Distributed Data Storage with Minimum Storage Regenerating Codes - Exact and Functional Repair are Asymptotically Equally Efficient
The problem of interest in this paper is to minimize the bandwidth required to exactly repair failed nodes in distributed storage systems. It is well known that Maximum Distance Separable (MDS) codes can be used to reliably store data in distributed storage nodes. The authors consider a set up where a file of size M is stored in n distributed storage nodes, using an (n; k) Minimum Storage Regenerating (MSR) code, i.e., a Maximum Distance Separable (MDS) code that also allows efficient exact-repair of any failed node. The MDS property ensures that the original file can be reconstructed even if any n - k storage nodes fail.