Non-order-preserving Index for Encrypted Database Management System

Data confidentiality is concerned in Database-as-a-Service (DBaaS) model. Encrypted database management system (EDBMS) addresses this concern by the data owner (DO) encrypting its private data before storing them in the database hosted by a third party service provider (SP). Indexing at SP over encrypted data is not straightforward. Most existing indexing methods are either order-preserving, or requiring DO to involve in query computation. Order-preserving index is vulnerable to inference analysis. Having DO to compute query beats the purpose of DBaaS model which is to delegate the database works of DO to SP. We developed a non-order-preserving indexing method that does not require DO's involvement in query processing at SP. Our empirical study shows that our indexing method can reduce selection processing cost by an order of magnitude compared to the case without the index.