Protecting Data In Cloud Storage

Several cloud storage systems exist today in which data are moved to a remotely located cloud server. Cloud faithfully stores the data and return back to the owner whenever needed. But there is no guarantee that data stored in the cloud are secured and not altered by the cloud or Third Party Auditor (TPA). The resources can be rapidly deployed with great efficiency and minimal management overhead. Since cloud is an insecure computing platform from the view point of the cloud users, the system must design mechanisms that not only protect sensitive information by enabling computations with encrypted data, but also protect users from malicious behaviors by enabling the validation of the computation result. In order to overcome the threat of integrity of data, the user must be able to use the assist of a TPA. The TPA has experience in checking integrity of the data, that clouds users does not have, and that is difficult for the owner to check.Project purpose:we are often limited by the resources at the cloud server as well as at the client. Given that the data sizes are large and are stored at remote servers, accessing the entire file can be expensive in I/O costs to the storage server. Also transmitting the file across the network to the client can consume heavy bandwidths. Since growth in storage capacity has far outpaced the growth in data access as well as network bandwidth, accessing and transmitting the entire archive even occasionally greatly limits the scalability of the network resources. Furthermore, the I/O to establish the data proof interferes with the on-demand bandwidth of the server used for normal storage and retrieving purpose.Project scope:Cloud storing its data file F at the client should process it and create suitable meta-data which is used in the later stage of verification the data integrity at the cloud storage. When checking for data integrity the client queries the cloud storage for suitable replies based on which it concludes the integrity of its data stored in the client, our data integrity protocol the verifier needs to store only a single cryptographic key-irrespective of the size of the data file F-and two functions which generate a random sequence. The verifier does not store any data with it. The verifier before storing the file at the archive preprocesses the file and appends some meta-data to the file and stores at the archive. System feature:The scheme was developed to reduce the computational and storage overhead of the client as well also minimizes the computational overhead of the cloud storage server. We also minimized the size of the proof of data integrity so as to reduce the network bandwidth consumption. Hence the storage at the client is very much minimal compared to all other schemes that were developed. Hence this scheme proves advantageous to thin clients like PDAs and mobile phones. The operation of encryption of data generally consumes a large computational power. In our scheme the encrypting process is very much limited to only a fraction of the whole data thereby saving on the computational time of the client. Many of the schemes proposed earlier require the archive to perform tasks that need a lot of computational power to generate the proof of data integrity. But in our scheme the archive just need to fetch and send few bits of data to the client.