Concurrent regenerating codes

To reduce multiple-failure repair traffic in erasure coded storage systems, Patrick Lee et al. introduce concurrent framework-based minimal-storage regenerating codes (RGCs). The approach is simpler and more practical than the cooperative mechanism in non-fully distributed environment. This study unifies such class of codes as concurrent RGC and further studies the characteristics by analysing the cut-based information flow graph. The authors present a general storage-bandwidth tradeoff and give closed-form expressions for the points on the curve including the minimal-bandwidth point. They show that the concurrent RGC can be constructed by reforming the existing single-node RGC or multiple-node cooperative RGC. Moreover, a connection to strong-maximum distance separable is also analysed.