Construction of substripe-added piggybacking codes

Abstract:

To address the issues of large repair degree, high repair bandwidth of parity nodes, and the inability to achieve fast repair of multiple nodes in existing piggybacking codes, a construction scheme of substripe-added piggybacking (SAP) codes is proposed in this paper. Based on maximum distance separable (MDS) codes, the proposed SAP codes extend the substripe, embed the data blocks of the information nodes by region regularly, and place the data blocks of the parity nodes using cyclic shifts. Through theoretical derivations, the average repair bandwidth rates and average repair degree rates of information nodes and parity nodes in SAP are determined. Finally, SAP is compared with RSR-I, RSR-II, and OOP in terms of three aspects: storage overhead, repair bandwidth overhead, and repair degree. The results show that, compared with RSR-I, RSR-II, and OOP, the SAP coding scheme not only achieves optimal repair degree but also significantly reduces parity node repair bandwidth while maintaining low information node repair bandwidth. Additionally, it enables rapid repair of multiple parity node failures, effectively addressing the issue of excessively high repair bandwidth in multiple parity node failures. The SAP coding proposed in this paper significantly improves the data recovery efficiency of piggybacking codes. In particular, a fast repair algorithm is provided to address multiple parity node failures, offering an effective approach for optimizing the piggybacking codes.