Public integrity auditing for dynamic regenerating code based cloud storage

To protect cloud data against corruption, enabling data integrity checking along with error recovery becomes quite critical. Recently, regenerating code has caught researchers' attention due to low repair traffic while preserving fault tolerance. Existing integrity checking schemes for regenerating code storage only support static data and have high auditing cost, which are not suitable for practical application. In this work, We propose a public auditing scheme for regenerating code based cloud storage supporting data dynamics. Our scheme allows the auditor to check the integrity of data stored across multiple servers and identify the location of corrupted data when data corruption is detected within one round. To support data dynamics, we design a novel update method based on matrix and index mechanism. The update method support multiple update requests performed in batch way without downloading and re-coding the data file and re-computing the data tags, such that the communication and computation cost can be greatly reduced. Theoretic analysis and experimental results show the security and efficiency of our proposed scheme.