A Cloud-User Watermarking Protocol Protecting the Right to Be Forgotten for the Outsourced Plain Images

This article describes how cloud storage dramatically benefits people in freeing up their local storage space, while bringing the separation of the data ownership and private manipulation. Hence, it is difficult for the cloud user to make sure that the cloud storage provider (CSP) has obeyed the request of deletion to remove all corresponding data. To solve the issue technically, this article proposes an interactive cloud-user watermarking protocol (CUW) based on the homomorphic encryption. To meet security requirements, the encrypted watermark is embedded into encrypted data. Moreover, to enjoy the convenient cloud services, the uploaded data is eventually stored in the cloud server in the form of plain text. The performance of the CUW protocol is evaluated through a prototype implementation.