HAZY KEYWORD HUNT OVER FACTS IN CLOUD COMPUTING.

Cloud Computing has been envisioned as the next-generation architecture of IT Enterprise. It moves the application software and databases to the centralized large data centers, where the management of the data and services may not be fully trustworthy. This unique paradigm brings about many new security challenges, which have not been well understood. This work studies the problem of ensuring the integrity of data storage in Cloud Computing. Controversies on privacy, however, have been incessantly presented as outsourcing of sensitive information including e-mails, health history and personal photos is explosively expanding. Reports of data loss and privacy breaches in cloud computing systems appear from time to time. Searchable symmetric encryption allows retrieval of encrypted data over cloud. In this paper, I focus on addressing data privacy issues using SSE. For the first time, we formulate the privacy issue from the aspect of similarity relevance and scheme robustness. I observe that server-side ranking based on orderpreserving encryption inevitably leaks data privacy. In this paper, then introduce the concepts of similarity relevance and scheme robustness to formulate the privacy issue in searchable encryption schemes, and then solve the insecurity problem by proposing a two-round searchable encryption scheme.