Querying Encrypted Graph Databases

We present an approach to execution of queries on encrypted graph databases. The approach is inspired by CryptDB system for relational DBs (R. A. Popa et al). Before processing a graph query is translated into encrypted form which then executed on a server without decrypting any data; the encrypted results are sent back to a client where they are finally decrypted. In this way data privacy is protected at the server side. We present the design of the system and empirical data obtained by experimentation with a prototype, implemented for Neo4j graph DBMS and Cypher query language, utilizing Java API. We report the efficiency of query execution for various types of queries on encrypted and non-encrypted Neo4j graph databases.