Storage and Repair Bandwidth Tradeoff for Distributed Storage Systems with Clusters and Separate Nodes

TL;DR

This paper investigates the optimal balance between storage and repair bandwidth in distributed storage systems with clusters and separate nodes, proposing a new code construction and analyzing the impact of separate nodes.

Contribution

It introduces a generalized tradeoff analysis for cluster DSSs under various parameters and presents a regenerating code construction achieving the optimal tradeoff.

Findings

Derived the optimal storage-repair bandwidth tradeoff for cluster DSSs.

Proposed a regenerating code construction for specific parameters.

Analyzed the effect of separate nodes on the tradeoff.

Abstract

The optimal tradeoff between node storage and repair bandwidth is an important issue for distributed storage systems (DSSs). As for realistic DSSs with clusters, when repairing a failed node, it is more efficient to download more data from intra-cluster nodes than from cross-cluster nodes. Therefore, it is meaningful to differentiate the repair bandwidth from intra-cluster and cross-cluster. For cluster DSSs the tradeoff has been considered with special repair assumptions where all the alive nodes are utilized to repair a failed node. In this paper, we investigate the optimal tradeoff for cluster DSSs under more general storage/repair parameters. Furthermore, a regenerating code construction strategy achieving the points in the optimal tradeoff curve is proposed for cluster DSSs with specific parameters as a numerical example. Moreover, the influence of separate nodes for the tradeoff is also considered for DSSs with clusters and separated nodes.