Verification of Multi-owner Shared Data with User Revocation and Collusion Resistance in Cloud Computing

Cloud enables its users to easily store and share the data with each other. Due to the security threats in a cloud, users are not assured about the integrity of their data. Users are recommended to compute the signatures on their data for the verification of integrity. Many mechanisms are proposed to verify the integrity of the single owner shared data rather than multi-owner data. Proposed system provides public auditing on multi-owner shared data. When user is revoked from the group, blocks signed by revoked user must be resigned. Proposed system also provides efficient user revocation with collusion resistance i.e. even if cloud colludes with any users; it is not able to learn the contents of the stored data