A Privacy Preserving Mechanism for Integrity Auditing and Data Sharing

With cloud storage services, users can store huge amount of data and share their data with others. This leads to security and integrity problems. Data on the web can be manipulated and corrupted and therefore will lose its integrity. To avoid this, data verification was introduced, which is achieved by using a technique called integrity auditing, through which verification of multiple data of a user is performed at a time. This paper avails a shared environment in which the data owner uploads the data and the users in that environment access it. In order to provide security to the uploaded data, Advanced Encryption Standard (AES) is used by the data owner to store encrypted data in cloud server. AES uses a 16 bit key which is sent to users through Simple Mail Transfer Protocol (SMTP), using which the users can retrieve the required data. A public auditor challenges the cloud server to prove the integrity of data stored by the data owner and verifies the integrity of data by using the proof generated by the server. Message Digest (MD5) generates a hash value which is used by public auditor to verify the integrity of data. Thus, this paper aims for providing privacy preserving mechanism using cryptographic techniques for integrity auditing and data sharing, and the performance analysis shows the efficiency of the mechanism when auditing data integrity.