Abstract—In cloud computing, clients usually outsource their data to the cloud storage servers to reduce the management costs. While those data may contain sensitive personal information, the cloud servers cannot be fully trusted in protecting them. Encryption is a promising way to protect the confidentiality of the outsourced data, but it also introduces much difficulty to performing effective searches over encrypted information. Most existing works do not support efficient searches with complex query conditions, and care needs to be taken when using them because of the potential privacy leakages about the data owners to the data users or the cloud server. In this paper, using online Personal Health Record (PHR) as a case study, we first show the necessity of search capability authorization that reduces the privacy exposure resulting from the search results, and establish a scalable framework for Authorized Private Keyword Search (APKS) over encrypted cloud data. We then propose two novel solutions for APKS based on a recent cryptographic primitive, Hierarchical Predicate Encryption (HPE). Our solutions enable efficient multi-dimensional keyword searches with range query, allow delegation and revocation of search capabilities. Moreover, we enhance the query privacy which hides users ’ query keywords against the server. We implement our scheme on a modern workstation, and experimental results demonstrate its suitability for practical usage. I.

Abstract—To ensure security, encryption techniques play a major role when data are outsourced to the cloud. Problem of retrieving the data from the cloud servers is considered. Many searching techniques are used for retrieving the data. This study focused on a set of keyword based search algorithms. It provides secure data retrieval with high efficiency. It concludes Ranked Searchable Symmetric Encryption (RSSE) scheme meant to be best methodology for searching the encrypted data.

Abstract — The increase in technology has brought forth many adversaries especially into the world of cloud computing. With the coming of cloud computing, the users can access data remotely from anywhere at any time and pay only for what they are using. Cloud Service Providers (CSP) play a great role in providing data security, but is it secure enough? This is a question that has changed the perspective of how clients see their CSP’s. A sufficient number of solutions have been offered to make the retrieval of data from the CSP in an efficient and secure manner, even while using a thin client. In this survey different keyword searching techniques are studied, to discover the best solution for retrieval of emails or files with increased security.

The 20th ACM Conference on Computer and Communications Security (CCS),

Abstract. Keyword search on encrypted data enables one to search key-word ciphertexts without compromising keyword security. We further in-vestigate this problem and propose a novel variant, dubbed certificateless keyword search on encrypted data (CLKS). CLKS not only supports key-word search on encrypted data, but also brings promising features due to the certificateless cryptography. In contrast to the certificated-based keyword search, CLKS requires no validation on the trustworthy of the