Programmable Order-Preserving Secure Index for Encrypted Database Query

The database services on cloud are appearing as an attractive way of outsourcing databases. When a database is deployed on a cloud database service, the data security and privacy becomes a big concern for users. A straightforward way to address this concern is to encrypt the database. However, an encrypted database cannot be easily queried. In this paper, we propose an order-preserving scheme for indexing encrypted data, which facilitates the range queries over encrypted databases. The scheme is secure since it randomizes each index with noises, such that the original data cannot be recovered from indexes. Moreover, our scheme allows the programmability of basic indexing expressions and thus the distribution of the original data can be hidden from the indexes.