Toward Privacy-Assured Cloud Data Services with Flexible Search Functionalities

User privacy has been a major concern against the widespread adoption of the cloud technology. A full-fledged cloud data service should effectively support data utilization tasks, especially flexible data search functionalities, while simultaneously achieve user privacy assurance and meet practical system-level performance requirements. In this position paper, we identify the importance and challenges of designing privacy-assured, \textit{flexible} and \textit{practically efficient} search mechanisms for outsourced cloud data services. In particular, we focus on two representative types of flexible search functionalities: ranked keyword search, and search over structured data. Although these functionalities are already prevalent in information retrieval in the plaintext domain, realizing them in the encrypted domain requires non-trivial effort and is relatively new. In light of this, we first describe several existing technical approaches proposed by us and other researchers, and identify their advantages and limitations. We also discuss the open research directions and provide some possible ideas for further investigation. We believe the presented results will inspire more research towards making privacy-assured search in the cloud practical and useful.

[1]  Thomas Ristenpart,et al.  Proceedings of the 3rd ACM workshop on Cloud computing security workshop , 2011, CCS 2011.

[2]  Kristin E. Lauter,et al.  Cryptographic Cloud Storage , 2010, Financial Cryptography Workshops.

[3]  Mihir Bellare,et al.  Deterministic and Efficiently Searchable Encryption , 2007, CRYPTO.

[4]  Markus Jakobsson,et al.  Controlling data in the cloud: outsourcing computation without outsourcing control , 2009, CCSW '09.

[5]  Craig Gentry,et al.  Non-interactive Verifiable Computing: Outsourcing Computation to Untrusted Workers , 2010, CRYPTO.

[6]  Brent Waters,et al.  Secure Conjunctive Keyword Search over Encrypted Data , 2004, ACNS.

[7]  Rafail Ostrovsky,et al.  Public Key Encryption with Keyword Search , 2004, EUROCRYPT.

[8]  Nikos Mamoulis,et al.  Secure kNN computation on encrypted databases , 2009, SIGMOD Conference.

[9]  Rafail Ostrovsky,et al.  Cryptography from Anonymity , 2006, 2006 47th Annual IEEE Symposium on Foundations of Computer Science (FOCS'06).

[10]  Andrew Chi-Chih Yao,et al.  Protocols for secure computations , 1982, FOCS 1982.

[11]  Cong Wang,et al.  Privacy-Preserving Query over Encrypted Graph-Structured Data in Cloud Computing , 2011, 2011 31st International Conference on Distributed Computing Systems.

[12]  Randy H. Katz,et al.  Above the Clouds: A Berkeley View of Cloud Computing , 2009 .

[13]  Siani Pearson,et al.  Privacy, Security and Trust Issues Arising from Cloud Computing , 2010, 2010 IEEE Second International Conference on Cloud Computing Technology and Science.

[14]  Marianne Winslett,et al.  Zerber: r-confidential indexing for distributed documents , 2008, EDBT '08.

[15]  Rafail Ostrovsky,et al.  Software protection and simulation on oblivious RAMs , 1996, JACM.

[16]  Ming Li,et al.  Authorized Private Keyword Search over Encrypted Data in Cloud Computing , 2011, 2011 31st International Conference on Distributed Computing Systems.

[17]  Nathan Chenette,et al.  Order-Preserving Symmetric Encryption , 2009, IACR Cryptol. ePrint Arch..

[18]  Dawn Xiaodong Song,et al.  Practical techniques for searches on encrypted data , 2000, Proceeding 2000 IEEE Symposium on Security and Privacy. S&P 2000.

[19]  Jonathan Katz,et al.  Predicate Encryption Supporting Disjunctions, Polynomial Equations, and Inner Products , 2008, Journal of Cryptology.

[20]  Cong Wang,et al.  Efficient verifiable fuzzy keyword search over encrypted data in cloud computing , 2013, Comput. Sci. Inf. Syst..

[21]  Rafail Ostrovsky,et al.  Searchable symmetric encryption: Improved definitions and efficient constructions , 2011, J. Comput. Secur..

[22]  Cong Wang,et al.  Towards Secure and Effective Utilization over Encrypted Cloud Data , 2011, 2011 31st International Conference on Distributed Computing Systems Workshops.

[23]  Brent Waters,et al.  Conjunctive, Subset, and Range Queries on Encrypted Data , 2007, TCC.

[24]  Vinod Vaikuntanathan,et al.  Can homomorphic encryption be practical? , 2011, CCSW '11.

[25]  Cong Wang,et al.  Privacy-Preserving Multi-Keyword Ranked Search over Encrypted Cloud Data , 2014 .

[26]  Melissa Chase,et al.  Structured Encryption and Controlled Disclosure , 2010, IACR Cryptol. ePrint Arch..

[27]  Craig Gentry,et al.  Fully homomorphic encryption using ideal lattices , 2009, STOC '09.

[28]  Radu Sion,et al.  On securing untrusted clouds with cryptography , 2010, WPES '10.

[29]  Eu-Jin Goh,et al.  Secure Indexes , 2003, IACR Cryptol. ePrint Arch..

[30]  Cong Wang,et al.  Privacy-preserving multi-keyword ranked search over encrypted cloud data , 2011, 2011 Proceedings IEEE INFOCOM.

[31]  Cong Wang,et al.  Secure Ranked Keyword Search over Encrypted Cloud Data , 2010, 2010 IEEE 30th International Conference on Distributed Computing Systems.

[32]  Philip S. Yu,et al.  Feature-based similarity search in graph structures , 2006, TODS.