A Practical Multi-Database Quantum Private Queries Protocol

This paper,based on the QKD technology which is mature now,proposes a practical QPQ protocol for multi-database retrieval optimized for current multi-databases in cloudy storage. For different sizes of the database,by adjusting the parameters θ and k,the information can be retrieved,while the safety of database and privacy of the user are ensured. Performance analyses indicate that the protocol has a low communication complexity and a high success ratio in information retrieval,and is easy to implement.