Research On Data Secure Storage And Secure Deletion Method Based On RS Erasure Code

In the era of big data, cloud storage service is becoming increasingly popular. The complexity of cloud storage environment and inadequate data security and privacy protection have caused mass data loss incident. Designing an efficient and secure data storage solution and data deletion program in a cloud storage system has important scientific significance and practical value.The main work of this paper includes the following two aspects:(1) Method of data security storage optimizationDemanding for efficiency in data storage overhead and data fault-tolerance capabilities in cloud storage environment, this paper uses erasure coding technology for data storage, and cryptographic means for data confidentiality. This paper proposes two key management algorithms based on Shamir's Secret Sharing and Rabin's Information Dispersal Algorithms, which reduce encryption key management complexity and improve the security of the encryption key, thereby improving the security of data storage.(2) Data secure deletion method inquiryWe discuss data secure deletion methods under the trusted third party and the untrusted third-party. In the trusted third party storage platforms, according to the(k, n) threshold scheme theory and characteristic of data which is processed by erasure codes, remove the file encryption key result in the data cannot decrypt from ciphertext, so get the purpose of the data completely deletion. In non-trusted third party storage platforms, due to non-credibility cloud data manipulation, design a method of two sides' control of the key information based on the user end and the Distribute Hash Table network, so long as either the key remove from the alternative size, cloud data cannot be decrypted from ciphertext, so can safely remove the data.Based on previous research, this paper implements the prototype system which integrate secure data storage and secure data deletion based on RS erasure code. The results shows that, compared to Shamir method, Shamir-RS method improves encoding performance significantly and ensures data security; compared to Rabin method, DA-RS method increased data security significantly with little performance decrease.