Research On The Integrity Audit Of Cloud Data For Multiple Backup Storage And Deduplication Storage

Recently,cloud storage is becoming increasingly prevalent.It also brings some new security issues.For example,users might not know when their data suffer from vicious damages,because they lose direct control of their data.In addition,the way of the data stored on the cloud varies with the users demand.Once the cloud suffers from some irresistible disasters,users may lose some important data permanently.As we all know,the multiple-replica cloud storage and cloud storage supporting data deduplication are two hot spots.Aiming at a number of problems in the current schemes,we propose the following four schemes with new properties:(1)We propose a scheme that provable multiple-replica dynamic data possession for big data storage in cloud computing.In our scheme,we make use of algebraic signature to generate authenticator for each data block.Meanwhile,we design a new data structure to efficiently support full dynamic data operations.(2)We propose a scheme that enables secure auditing and deduplicating data without owner-relationship exposure in cloud storage.The difference from previous schemes is that the cloud cannot know the relationship of the data owners possessing the same file.In our scheme,the cloud only needs to store one authenticator for each file block.The storage overhead is independent of the number of data owners.In our scheme,the authenticator is only generated by the initial data owner,who is the first uploader of this file.Subsequent data owners do not need to generate authenticators any longer.(3)We propose a new cloud storage data integrity auditing scheme which supports data deduplication.In this scheme,in order to greatly reduce the computation overhead of user,we use algebraic signature to generate authenticator for each block.Moreover,we use re-encryption to solve the problem of dynamic ownership changing.If a user has executed deletion or modification operation,then he will not be the owner of this data any longer,and cannot access the data.(4)We propose a secure cloud storage auditing for different popularity deduplicating data scheme.In this scheme,we consider the different levels of protection requested by data.For the unpopular data,we guarantee their data privacy in a high level by using the semantically secure encryption schemes.