Research Article

Security Analysis and Improvements on a Remote Integrity Checking Scheme for Regenerating-Coding-Based Distributed Storage

Figure 2

Repairing a failed node [19]: the original file consists of four blocks—, and . A (4, 2) MDS (maximum distance separable) code is applied such that any two healthy nodes can restore the original file while the repair bandwidth is 1 for each helper node. The repair involves combining blocks and the total repair bandwidth consisting of 3 blocks instead of 4, where 4 is the amount of blocks needed to reconstruct the whole file.