Hi Shubhangi,
Data Integrity proof means that the data which is stored on the cloud by the client is not compromised. One of the important concerns that need to be addressed is to assure the customer of the integrity i.e. correctness of the data in the cloud. As the data is physically not accessible to the user the cloud should provide a way for the user to check if the integrity of his data is maintained or is compromised. and this can be done in ways such as:
A way in which the client can periodically check and verify the data.
The cloud can add verification metadata to the file before storing that the verification before reading the file can be checked as the data storage in the cloud storage archives can be modified by the archive and thereby the integrity of the data is assured.
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