Abstract: In order to enable users to understand the integrity of cloud documents, a new retrievability proof scheme M-POR ( Proof of Retrievability-Based Message Authentication Codes) is proposed based on MACs (Message Authentication Codes). The MACs are generated by data blocks as authenticators, which can verify data integrity and locate the error data block. An original document is uploaded to the cloud server after encoding. Users can verify data integrity by using challenge-response-verification algorithms. The error-correcting code is introduced in encoding. If the error data is less than the threshold, the data can be recovered. Performance analysis shows that M-POR scheme can provide data integrity proof, and has low storage cost and calculation cost.

Key words: data integrity; , proofs of retrievability; , message authentication code; , cloud storage