Order preserving encryption for wide column stores

Abstract

Order-preserving encryption (OPE) allows encrypting without losing information about the order relation between the encrypted data items. Thus, the execution of compare, order and grouping operations can be done like on plaintext data. In particular it allows databases to do range queries over encrypted data, which is a useful feature especially for cloud databases that usually run in untrusted environments. Several OPE schemes have been proposed in the last years, but almost none of them are used in real world scenarios. While OPE was at least implemented for some SQL- based prototype systems before (e.g. [Po11, Tu13], our work identifies the practical requirements for utilizing OPE in existing NoSQL cloud database technologies. It also provides runtime analyses of two popular OPE schemes combined with two popular NoSQL wide column store databases.