J4 ›› 2015, Vol. 42 ›› Issue (5): 33-37+74.doi: 10.3969/j.issn.1001-2400.2015.05.006

• Original Articles • Previous Articles     Next Articles

Low complexity quantum private queries protocol

HE Xiaoyun;PEI Changxing;YI Yunhui   

  1. (State Key Lab. of Integrated Service Networks, Xidian Univ., Xi'an  710071, China)
  • Received:2014-05-12 Online:2015-10-20 Published:2015-12-03
  • Contact: HE Xiaoyun E-mail:thxy@msn.com

Abstract:

Private information retrieval(PIR) is an important privacy protection issue of secure multi-party computation, but the PIR protocols based on classical cryptography are vulnerable because of new technologies,such as quantum computing and cloud computing. The quantum private queries(QPQ) protocols available, however, has a high complexity and is inefficient in the face of large database. This paper, based on the QKD technology which is mature now, proposes a novel QPQ protocol utilizing the key dilution and auxiliary parameter. Only N quits are required to be sent in the quantum channel to generate the raw key, then the straight k bits in the raw key are added bitwise to dilute the raw key, and a final key is consequently obtained to encrypt the database. By flexible adjusting of auxiliary parameters θ and k, privacy is secured and the query success ratio is improved. Feasibility and performance analyses indicate that the protocol has a high success ratio in first-trial query and is easy to implement, and that the communication complexity of O(N) is achieved.

Key words: quantum private queries, quantum key distribution, communication complexity, database security, user privacy

CLC Number: 

  • TP918