BMCloud: Minimizing Repair Bandwidth and Maintenance Cost in Cloud Storage

Algorithm 1

Algorithm E Code: encode algorithm of the exact layer.

1: Requirements:

2:  Native chunks;

3:  Encoding request;

4:  Main parameters (𝑛,𝑘,𝑠) in F-MSR code and E  Code;

5: Step  1. System initialization

6: Step  2. F-MSR (𝑛,𝑘) encoding

7:  (a): Generate random encoding coefficient vectors;

8:  (b): If MDS is satisfied

9:    then generate an encoding matrix from then coding coefficient vectors;

10:    else return to a;

11:  (c): Compute the product of encoding matrix and native

12:   chunks as F-MSR chunk;

13: Step  3. E Code (𝑛,𝑠) encoding

14:  (a): Divide each F-MSR chunk into stripes and strips;

15:  (b): For stripe A in F-MSR chunks

16:    Calculate the parity strip of this stripe;

17:    Save the parity strip in certain position

18:  (c): Consolidate the strips into extended F-MSR chunks