Making Query Execution Over Encrypted Data Practical

The benefits of data outsourcing continue to grow, however owners of sensitive data cannot take full advantage due to its risk profile. Encrypted query processing promises to change this situation and allow data owners to securely outsource their sensitive data: data is encrypted, installed in a database on a remote (e.g., cloud) server, and standard queries are processed against the remote encrypted data. Correct query answers are returned without ever exposing plaintexts or decryption keys at the server. This chapter addresses three key challenges to realizing, as a practical option, the promise of encrypted query processing: handling query operations which cannot execute in ciphertext, implementing a working system, and achieving acceptable query performance.