Research On Safe Deduplication Method In Cloud Storage Environment

Due to the limitations of local resources and sharply increasing costs in hardware maintenance,users tend to outsource local data to cloud servers for storage.With the increasing of cloud storage users,the size of stored data in cloud is proportional to the number of users,which leads to a large amount of storage redundancy.Therefore,deduplication receives great attention from both academia and industry.In order to protect data privacy,users tend to encrypt their data with their own keys,which wastes a lot of storage space and complicates cross-user data sharing operations.Under the premise of ensuring data privacy,how to effectively perform deduplication in semi-trusted cloud storage environments becomes one of the primary issues in cloud computing security.To achieve secure deduplication of encrypted data,three solutions were put forward in this thesis.(1)On the basis of bilinear mapping and group signature scheme,a verifiable client-side data deduplication method is proposed.This scheme can judge and verify the correctness of operations,which doesn't require any online trusted third party.(2)On the basis of multi-party computation principles and bloom filter,a verifiable secure data deduplication based on user-defined security requirement is proposed.By introducing the attribute-based security requirement mechanism,it ensures the privacy of data and prevents malicious users from conducting eavesdropping attack.(3)On the basis of bilinear mapping and proxy re-encryption,an ownership verifiable and security data deduplication is proposed.There are only two entities,cloud server and users,without any real-time online third party.It secures the data deduplication process.It also ensures that only authorized users can obtain data.