{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T01:27:39Z","timestamp":1780536459223,"version":"3.54.1"},"reference-count":111,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,4,8]],"date-time":"2020-04-08T00:00:00Z","timestamp":1586304000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Shandong Provincial Key Research and Development Program of China","award":["2018CXGC0701"],"award-info":[{"award-number":["2018CXGC0701"]}]},{"name":"National Natural Science Foundation of China (NSFC)","award":["No. 61972050"],"award-info":[{"award-number":["No. 61972050"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>With the popularization of cloud computing, many business and individuals prefer to outsource their data to cloud in encrypted form to protect data confidentiality. However, how to search over encrypted data becomes a concern for users. To address this issue, searchable encryption is a novel cryptographic primitive that enables user to search queries over encrypted data stored on an untrusted server while guaranteeing the privacy of the data. Public key encryption with keyword search (PEKS) has received a lot of attention as an important branch. In this paper, we focus on the development of PEKS in cloud by providing a comprehensive research survey. From a technological viewpoint, the existing PEKS schemes can be classified into several variants: PEKS based on public key infrastructure, PEKS based on identity-based encryption, PEKS based on attribute-based encryption, PEKS based on predicate encryption, PEKS based on certificateless encryption, and PEKS supporting proxy re-encryption. Moreover, we propose some potential applications and valuable future research directions in PEKS.<\/jats:p>","DOI":"10.3390\/e22040421","type":"journal-article","created":{"date-parts":[[2020,4,9]],"date-time":"2020-04-09T03:40:19Z","timestamp":1586403619000},"page":"421","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["Public Key Encryption with Keyword Search in Cloud: A Survey"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7024-6848","authenticated-orcid":false,"given":"Yunhong","family":"Zhou","sequence":"first","affiliation":[{"name":"State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing 100876, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Na","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing 100876, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6626-9120","authenticated-orcid":false,"given":"Yanmei","family":"Tian","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing 100876, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dezhi","family":"An","sequence":"additional","affiliation":[{"name":"School of Cyber Security, Gansu University of Political Science and Law, Lanzhou 730070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8418-1897","authenticated-orcid":false,"given":"Licheng","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing 100876, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Mell, P., and Grance, T. (2011). The NIST Definition of Cloud Computing, National Institute of Standards and Technology.","DOI":"10.6028\/NIST.SP.800-145"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"599","DOI":"10.1016\/j.future.2008.12.001","article-title":"Cloud computing and emerging IT platforms: Vision, hype, and reality for delivering computing as the 5th utility","volume":"25","author":"Buyya","year":"2009","journal-title":"Future Gener. Comput. Syst."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2434","DOI":"10.1109\/TPDS.2019.2915073","article-title":"Distributed Personal Cloud Storage without Third Parties","volume":"30","author":"Konstantopoulos","year":"2019","journal-title":"IEEE Trans. Parallel Distrib. Syst."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Aloqaily, M., Kantarci, B., and Mouftah, H.T. (2015, January 4\u20137). A generalized framework for quality of experience (QoE)-based provisioning in a vehicular cloud. Proceedings of the 2015 IEEE International Conference on Ubiquitous Wireless Broadband (ICUWB), Montreal, QC, Canada.","DOI":"10.1109\/ICUWB.2015.7324403"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"101842","DOI":"10.1016\/j.adhoc.2019.02.001","article-title":"An intrusion detection system for connected vehicles in smart cities","volume":"90","author":"Aloqaily","year":"2019","journal-title":"Ad Hoc Netw."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1109\/LSENS.2017.2752719","article-title":"Detection of known and unknown intrusive sensor behavior in critical applications","volume":"1","author":"Otoum","year":"2017","journal-title":"Ieee Sens. Lett."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Kamara, S., and Lauter, K. (2010, January 25\u201328). Cryptographic cloud storage. Proceedings of the 2010 International Conference on Financial Cryptography and Data Security, Tenerife, Canary Islands, Spain.","DOI":"10.1007\/978-3-642-14992-4_13"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"431","DOI":"10.1145\/233551.233553","article-title":"Software protection and simulation on oblivious RAMs","volume":"43","author":"Goldreich","year":"1996","journal-title":"J. ACM (JACM)"},{"key":"ref_9","unstructured":"Song, D.X., Wagner, D., and Perrig, A. (2000, January 14\u201317). Practical techniques for searches on encrypted data. Proceedings of the 2000 IEEE Symposium on Security and Privacy (SSP 2000), Berkeley, CA, USA."},{"key":"ref_10","first-page":"216","article-title":"Secure indexes","volume":"2003","author":"Goh","year":"2003","journal-title":"IACR Cryptol. Eprint Arch."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Chang, Y.C., and Mitzenmacher, M. (2005, January 7\u201310). Privacy preserving keyword searches on remote encrypted data. Proceedings of the International Conference on Applied Cryptography and Network Security, New York, NY, USA.","DOI":"10.1007\/11496137_30"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"895","DOI":"10.3233\/JCS-2011-0426","article-title":"Searchable symmetric encryption: Improved definitions and efficient constructions","volume":"19","author":"Curtmola","year":"2011","journal-title":"J. Comput. Secur."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Kamara, S., Papamanthou, C., and Roeder, T. (2012, January 16\u201318). Dynamic searchable symmetric encryption. Proceedings of the 2012 ACM conference on Computer and communications security, Raleigh, NC, USA.","DOI":"10.1145\/2382196.2382298"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Kamara, S., and Papamanthou, C. (2013, January 1\u20135). Parallel and dynamic searchable symmetric encryption. Proceedings of the International Conference on Financial Cryptography and Data Security, Okinawa, Japan.","DOI":"10.1007\/978-3-642-39884-1_22"},{"key":"ref_15","first-page":"1","article-title":"A survey of provably secure searchable encryption","volume":"47","author":"Hartel","year":"2014","journal-title":"Acm Comput. Surv. (Csur)"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1007\/BF03391580","article-title":"Secure searchable encryption: A survey","volume":"1","author":"Wang","year":"2016","journal-title":"J. Commun. Inf. Netw."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Pham, H., Woodworth, J., and Salehi, M.A. (2018). Survey on secure search over encrypted data on the cloud. arXiv.","DOI":"10.1002\/cpe.5284"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"e5201","DOI":"10.1002\/cpe.5201","article-title":"Searchable encryption: A survey on privacy-preserving search schemes on encrypted outsourced data","volume":"31","author":"Handa","year":"2019","journal-title":"Concurr. Comput. Pract. Exp."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1016\/j.future.2016.01.007","article-title":"Secure searches in the cloud: A survey","volume":"62","author":"Han","year":"2016","journal-title":"Future Gener. Comput. Syst."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Boneh, D., Di Crescenzo, G., Ostrovsky, R., and Persiano, G. (2004, January 2\u20136). Public key encryption with keyword search. Proceedings of the 2004 International conference on the theory and applications of cryptographic techniques, Interlaken, Switzerland.","DOI":"10.1007\/978-3-540-24676-3_30"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Boneh, D., and Franklin, M. (2001, January 19\u201323). Identity-based encryption from the Weil pairing. Proceedings of the 2001 Annual International Cryptology Conference, Santa Barbara, CA, USA.","DOI":"10.1007\/3-540-44647-8_13"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"586","DOI":"10.1137\/S0097539701398521","article-title":"Identity-based encryption from the Weil pairing","volume":"32","author":"Boneh","year":"2003","journal-title":"SIAM J. Comput."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Byun, J.W., Rhee, H.S., Park, H.A., and Lee, D.H. (2006, January 10\u201311). Off-line keyword guessing attacks on recent keyword search schemes over encrypted data. Proceedings of the 2006 Workshop on Secure Data Management, Seoul, Korea.","DOI":"10.1007\/11844662_6"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1016\/j.ins.2018.12.004","article-title":"Keyword guessing attacks on a public key encryption with keyword search scheme without random oracle and its improvement","volume":"479","author":"Lu","year":"2019","journal-title":"Inf. Sci."},{"key":"ref_25","unstructured":"Baek, J., Safavi-Naini, R., and Susilo, W. (2008, January 1\u20134). Public key encryption with keyword search revisited. Proceedings of the International conference on Computational Science and Its Applications, Perugia, Italy."},{"key":"ref_26","unstructured":"Zhang, Y., Katz, J., and Papamanthou, C. (2016, January 10\u201312). All your queries are belong to us: The power of file-injection attacks on searchable encryption. Proceedings of the 25th {USENIX} Security Symposium ({USENIX} Security 16), Austin, TX, USA."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Rhee, H.S., Park, J.H., Susilo, W., and Lee, D.H. (2009, January 10\u201312). Improved searchable public key encryption with designated tester. Proceedings of the 4th International Symposium on Information, Computer, and Communications Security, Sydney, Australia.","DOI":"10.1145\/1533057.1533108"},{"key":"ref_28","unstructured":"Park, D.J., Kim, K., and Lee, P.J. (2004, January 23\u201325). Public key encryption with conjunctive field keyword search. Proceedings of the 2004 International Workshop on Information Security Applications, Jeju Island, Korea."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Hwang, Y.H., and Lee, P.J. (2007, January 2\u20134). Public key encryption with conjunctive keyword search and its extension to a multi-user system. Proceedings of the 2007 International Conference on Pairing-Based Cryptography, Tokyo, Japan.","DOI":"10.1007\/978-3-540-73489-5_2"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1016\/j.jnca.2010.07.007","article-title":"An efficient public key encryption with conjunctive-subset keywords search","volume":"34","author":"Zhang","year":"2011","journal-title":"J. Netw. Comput. Appl."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Lv, Z., Hong, C., Zhang, M., and Feng, D. (2014, January 12\u201314). Expressive and secure searchable encryption in the public key setting. Proceedings of the 2014 International Conference on Information Security, Hong Kong, China.","DOI":"10.1007\/978-3-319-13257-0_21"},{"key":"ref_32","unstructured":"Tang, Q., and Chen, L. (2009, January 10\u201311). Public-key encryption with registered keyword search. Proceedings of the 2009 European Public Key Infrastructure Workshop, Pisa, Italy."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"716","DOI":"10.4304\/jcp.7.3.716-723","article-title":"An enhanced searchable public key encryption scheme with a designated tester and its extensions","volume":"7","author":"Hu","year":"2012","journal-title":"J. Comput."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1016\/j.ins.2013.03.008","article-title":"Public key encryption with keyword search secure against keyword guessing attacks without random oracle","volume":"238","author":"Fang","year":"2013","journal-title":"Inf. Sci."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"957","DOI":"10.1016\/j.ipl.2015.07.006","article-title":"On security against the server in designated tester public key encryption with keyword search","volume":"115","author":"Shao","year":"2015","journal-title":"Inf. Process. Lett."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Zhang, R., Xue, R., Yu, T., and Liu, L. (July, January 27). PVSAE: A public verifiable searchable encryption service framework for outsourced encrypted data. Proceedings of the 2016 IEEE International Conference on Web Services (ICWS), San Francisco, CA, USA.","DOI":"10.1109\/ICWS.2016.62"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.ins.2017.03.038","article-title":"An efficient public-key searchable encryption scheme secure against inside keyword guessing attacks","volume":"403","author":"Huang","year":"2017","journal-title":"Inf. Sci."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"7685","DOI":"10.1007\/s00500-018-3224-8","article-title":"An efficient and secure searchable public key encryption scheme with privacy protection for cloud storage","volume":"22","author":"Wu","year":"2018","journal-title":"Soft Comput."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Bellare, M., and Rogaway, P. (1993, January 3\u20135). Random oracles are practical: A paradigm for designing efficient protocols. Proceedings of the 1st ACM Conference on Computer and Communications Security, Fairfax, VA, USA.","DOI":"10.1145\/168588.168596"},{"key":"ref_40","unstructured":"Shamir, A. (1984, January 9\u201311). Identity-based cryptosystems and signature schemes. Proceedings of the 1984 Workshop on the Theory and Application of Cryptographic Techniques, Paris, France."},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Di Crescenzo, G., and Saraswat, V. (2007, January 9\u201313). Public key encryption with searchable keywords based on Jacobi symbols. Proceedings of the 2007 International Conference on Cryptology in India, Chennai, India.","DOI":"10.1007\/978-3-540-77026-8_21"},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Cocks, C. (2001, January 17\u201319). An identity based encryption scheme based on quadratic residues. Proceedings of the 2001 IMA International Conference on Cryptography and Coding, Cirencester, UK.","DOI":"10.1007\/3-540-45325-3_32"},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Tian, X., and Wang, Y. (2008, January 12\u201317). ID-based encryption with keyword search scheme from bilinear pairings. Proceedings of the 2008 4th International Conference on Wireless Communications, Networking and Mobile Computing, Dalian, China.","DOI":"10.1109\/WiCom.2008.2916"},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Camenisch, J., Kohlweiss, M., Rial, A., and Sheedy, C. (2009, January 18\u201320). Blind and anonymous identity-based encryption and authorised private searches on public key encrypted data. Proceedings of the 2009 International Workshop on Public Key Cryptography, Irvine, CA, USA.","DOI":"10.1007\/978-3-642-00468-1_12"},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Abdalla, M., Bellare, M., Catalano, D., Kiltz, E., Kohno, T., Lange, T., Malone-Lee, J., Neven, G., Paillier, P., and Shi, H. (2005, January 14\u201318). Searchable encryption revisited: Consistency properties, relation to anonymous IBE, and extensions. Proceedings of the 2005 Annual International Cryptology Conference, Santa Barbara, CA, USA.","DOI":"10.1007\/11535218_13"},{"key":"ref_46","unstructured":"Khader, D. (2007, January 26\u201329). Public key encryption with keyword search based on K-resilient IBE. Proceedings of the 2007 International Conference on Computational Science and Its Applications, Kuala Lumpur, Malaysia."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"391","DOI":"10.1007\/s12243-013-0398-z","article-title":"Efficient searchable ID-based encryption with a designated server","volume":"69","author":"Wu","year":"2014","journal-title":"Ann. Telecommun."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"359","DOI":"10.1007\/s12243-017-0574-7","article-title":"Efficient designated server identity-based encryption with conjunctive keyword search","volume":"72","author":"Lu","year":"2017","journal-title":"Ann. Telecommun."},{"key":"ref_49","doi-asserted-by":"crossref","unstructured":"Siad, A. (2012, January 7\u201310). Anonymous identity-based encryption with distributed private-key generator and searchable encryption. Proceedings of the 2012 5th International Conference on New Technologies, Mobility and Security (NTMS), Istanbul, Turkey.","DOI":"10.1109\/NTMS.2012.6208695"},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Emura, K., and Watanabe, Y. (2015, January 20\u201322). Keyword revocable searchable encryption with trapdoor exposure resistance and re-generateability. Proceedings of the 2015 IEEE Trustcom\/BigDataSE\/ISPA, Helsinki, Finland.","DOI":"10.1109\/Trustcom.2015.371"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"1012","DOI":"10.1007\/s11390-016-1676-9","article-title":"Secure channel free id-based searchable encryption for peer-to-peer group","volume":"31","author":"Wang","year":"2016","journal-title":"J. Comput. Sci. Technol."},{"key":"ref_52","unstructured":"Sahai, A., and Waters, B. (2005, January 22\u201326). Fuzzy identity-based encryption. Proceedings of the 2005 Annual International Conference on the Theory and Applications of Cryptographic Techniques, Aarhus, Denmark."},{"key":"ref_53","unstructured":"Zhao, F., Nishide, T., and Sakurai, K. (December, January 30). Multi-user keyword search scheme for secure data sharing with fine-grained access control. Proceedings of the 2011 International Conference on Information Security and Cryptology, Seoul, Korea."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1016\/j.future.2013.09.013","article-title":"A general transformation from KP-ABE to searchable encryption","volume":"30","author":"Han","year":"2014","journal-title":"Future Gener. Comput. Syst."},{"key":"ref_55","doi-asserted-by":"crossref","unstructured":"Wang, C., Li, W., Li, Y., and Xu, X. (2013). A ciphertext-policy attribute-based encryption scheme supporting keyword search function. Cyberspace Safety and Security, Springer.","DOI":"10.1007\/978-3-319-03584-0_28"},{"key":"ref_56","doi-asserted-by":"crossref","unstructured":"Zheng, Q., Xu, S., and Ateniese, G. (May, January 27). VABKS: Verifiable attribute-based keyword search over outsourced encrypted data. Proceedings of the IEEE INFOCOM 2014-IEEE Conference on Computer Communications, Toronto, Canada.","DOI":"10.1109\/INFOCOM.2014.6847976"},{"key":"ref_57","doi-asserted-by":"crossref","unstructured":"Liu, P., Wang, J., Ma, H., and Nie, H. (2014, January 8\u201310). Efficient verifiable public key encryption with keyword search based on KP-ABE. Proceedings of the 2014 Ninth International Conference on Broadband and Wireless Computing, Communication and Applications, Guangdong, China.","DOI":"10.1109\/BWCCA.2014.119"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"715","DOI":"10.1109\/TSC.2016.2542813","article-title":"KSF-OABE: Outsourced attribute-based encryption with keyword search function for cloud storage","volume":"10","author":"Li","year":"2016","journal-title":"IEEE Trans. Serv. Comput."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1186\/s13677-015-0034-8","article-title":"Attribute-based data retrieval with semantic keyword search for e-health cloud","volume":"4","author":"Yang","year":"2015","journal-title":"J. Cloud Comput."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"1274","DOI":"10.1109\/TIFS.2015.2405905","article-title":"White-box traceable ciphertext-policy attribute-based encryption supporting flexible attributes","volume":"10","author":"Ning","year":"2015","journal-title":"IEEE Trans. Inf. Forensics Secur."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"1187","DOI":"10.1109\/TPDS.2014.2355202","article-title":"Protecting your right: Verifiable attribute-based keyword search with fine-grained owner-enforced search authorization in the cloud","volume":"27","author":"Sun","year":"2014","journal-title":"IEEE Trans. Parallel Distrib. Syst."},{"key":"ref_62","doi-asserted-by":"crossref","unstructured":"Zhu, H., Mei, Z., Wu, B., Li, H., and Cui, Z. (2017). Fuzzy keyword search and access control over ciphertexts in cloud computing. Proceedings of the 2017 Australasian Conference on Information Security and Privacy, Springer.","DOI":"10.1007\/978-3-319-60055-0_13"},{"key":"ref_63","doi-asserted-by":"crossref","unstructured":"Miao, Y., Ma, J., Liu, X., Li, X., Jiang, Q., and Zhang, J. (2017). Attribute-based keyword search over hierarchical data in cloud computing. IEEE Trans. Serv. Comput.","DOI":"10.1109\/TSC.2017.2757467"},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"e3566","DOI":"10.1002\/dac.3566","article-title":"A based on blinded CP-ABE searchable encryption cloud storage service scheme","volume":"31","author":"Cao","year":"2018","journal-title":"Int. J. Commun. Syst."},{"key":"ref_65","unstructured":"Miao, Y., Liu, X., Choo, K.K.R., Deng, R.H., Li, J., Li, H., and Ma, J. (2019). Privacy-preserving attribute-based keyword search in shared multi-owner setting. IEEE Trans. Dependable Secur. Comput."},{"key":"ref_66","doi-asserted-by":"crossref","unstructured":"Katz, J., Sahai, A., and Waters, B. (2008). Predicate encryption supporting disjunctions, polynomial equations, and inner products. Proceedings of the Annual International Conference on the Theory and Applications of Cryptographic Techniques, Springer.","DOI":"10.1007\/978-3-540-78967-3_9"},{"key":"ref_67","doi-asserted-by":"crossref","unstructured":"Blundo, C., Iovino, V., and Persiano, G. (2010). Predicate encryption with partial public keys. Proceedings of the 2010 International Conference on Cryptology and Network Security, Springer.","DOI":"10.1007\/978-3-642-17619-7_21"},{"key":"ref_68","doi-asserted-by":"crossref","unstructured":"Zhu, B., Zhu, B., and Ren, K. (2011, January 5\u20139). PEKSrand: Providing predicate privacy in public-key encryption with keyword search. Proceedings of the 2011 IEEE International Conference on Communications (ICC), Kyoto, Japan.","DOI":"10.1109\/icc.2011.5962452"},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"191","DOI":"10.1007\/s00145-012-9119-4","article-title":"Predicate encryption supporting disjunctions, polynomial equations, and inner products","volume":"26","author":"Katz","year":"2013","journal-title":"J. Cryptol."},{"key":"ref_70","doi-asserted-by":"crossref","unstructured":"Zhang, Y., and Lu, S. (2014, January 3\u20137). POSTER: Efficient method for disjunctive and conjunctive keyword search over encrypted data. Proceedings of the 2014 ACM SIGSAC Conference on Computer and Communications Security, Scottsdale, AZ, USA.","DOI":"10.1145\/2660267.2662361"},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"2947","DOI":"10.1109\/TC.2016.2526000","article-title":"An efficient predicate encryption with constant pairing computations and minimum costs","volume":"65","author":"Kim","year":"2016","journal-title":"IEEE Trans. Comput."},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"5280806","DOI":"10.1155\/2019\/5280806","article-title":"Secure and efficient searchable public key encryption for resource constrained environment based on pairings under prime order group","volume":"2019","author":"Zhang","year":"2019","journal-title":"Secur. Commun. Netw."},{"key":"ref_73","doi-asserted-by":"crossref","unstructured":"Gay, R., M\u00e9aux, P., and Wee, H. (2015). Predicate encryption for multi-dimensional range queries from lattices. Proceedings of the 2015 IACR International Workshop on Public Key Cryptography, Springer.","DOI":"10.1007\/978-3-662-46447-2_34"},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"122078","DOI":"10.1109\/ACCESS.2019.2937846","article-title":"Searchable Public Key Encryption Supporting Semantic Multi-Keywords Search","volume":"7","author":"Zhang","year":"2019","journal-title":"IEEE Access"},{"key":"ref_75","doi-asserted-by":"crossref","unstructured":"Al-Riyami, S.S., and Paterson, K.G. (2003). Certificateless public key cryptography. Proceedings of the 2003 International Conference on the Theory and Application of Cryptology and Information Security, Springer.","DOI":"10.1007\/978-3-540-40061-5_29"},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1109\/CC.2014.7004528","article-title":"Certificateless public key encryption with keyword search","volume":"11","author":"Yanguo","year":"2014","journal-title":"China Commun."},{"key":"ref_77","doi-asserted-by":"crossref","unstructured":"Wu, T.Y., Meng, F., Chen, C.M., Liu, S., and Pan, J.S. (2016). On the security of a certificateless searchable public key encryption scheme. Proceedings of the 2016 International Conference on Genetic and Evolutionary Computing, Springer.","DOI":"10.1007\/978-3-319-48490-7_14"},{"key":"ref_78","doi-asserted-by":"crossref","unstructured":"Zheng, Q., Li, X., and Azgin, A. (2015). CLKS: Certificateless keyword search on encrypted data. Proceedings of the 2015 International Conference on Network and System Security, Springer.","DOI":"10.1007\/978-3-319-25645-0_16"},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"759","DOI":"10.1109\/TII.2017.2703922","article-title":"Certificateless searchable public key encryption scheme for industrial internet of things","volume":"14","author":"Ma","year":"2017","journal-title":"IEEE Trans. Ind. Inform."},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"413","DOI":"10.1016\/j.compeleceng.2017.05.014","article-title":"Certificateless searchable public key encryption scheme for mobile healthcare system","volume":"65","author":"Ma","year":"2018","journal-title":"Comput. Electr. Eng."},{"key":"ref_81","doi-asserted-by":"crossref","unstructured":"Islam, S.H., Obaidat, M.S., Rajeev, V., and Amin, R. (2017). Design of a certificateless designated server based searchable public key encryption scheme. Proceedings of the 2007 International Conference on Mathematics and Computing, Springer.","DOI":"10.1007\/978-981-10-4642-1_1"},{"key":"ref_82","doi-asserted-by":"crossref","first-page":"423","DOI":"10.1007\/s12243-018-00701-7","article-title":"Certificateless searchable public key authenticated encryption with designated tester for cloud-assisted medical Internet of Things","volume":"74","author":"Wu","year":"2019","journal-title":"Ann. Telecommun."},{"key":"ref_83","doi-asserted-by":"crossref","first-page":"1049","DOI":"10.1631\/FITEE.1700534","article-title":"Constructing pairing-free certificateless public key encryption with keyword search","volume":"20","author":"Lu","year":"2019","journal-title":"Front. Inf. Technol. & Electron. Eng."},{"key":"ref_84","doi-asserted-by":"crossref","unstructured":"Blaze, M., Bleumer, G., and Strauss, M. (1998). Divertible protocols and atomic proxy cryptography. Proceedings of the 1998 International Conference on the Theory and Applications of Cryptographic Techniques.","DOI":"10.1007\/BFb0054122"},{"key":"ref_85","doi-asserted-by":"crossref","first-page":"2576","DOI":"10.1016\/j.ins.2010.03.026","article-title":"Proxy re-encryption with keyword search","volume":"180","author":"Shao","year":"2010","journal-title":"Inf. Sci."},{"key":"ref_86","doi-asserted-by":"crossref","unstructured":"Yau, W.C., Phan, R.C.W., Heng, S.H., and Goi, B.M. (2010). Proxy re-encryption with keyword search: New definitions and algorithms. Security Technology, Disaster Recovery and Business Continuity, Springer.","DOI":"10.1007\/978-3-642-17610-4_17"},{"key":"ref_87","doi-asserted-by":"crossref","unstructured":"Zhong, W., Wang, X.A., Wang, Z., and Ding, Y. (2011, January 3\u20134). Proxy re-encryption with keyword search from anonymous conditional proxy re-encryption. Proceedings of the 2011 Seventh International Conference on Computational Intelligence and Security, Hainan, China.","DOI":"10.1109\/CIS.2011.217"},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"643","DOI":"10.1016\/j.jss.2011.09.035","article-title":"Further observation on proxy re-encryption with keyword search","volume":"85","author":"Wang","year":"2012","journal-title":"J. Syst. Softw."},{"key":"ref_89","doi-asserted-by":"crossref","unstructured":"Guo, L., Lu, B., Li, X., and Xu, H. (2013, January 14\u201315). A verifiable proxy re-encryption with keyword search without random oracle. Proceedings of the 2013 Ninth International Conference on Computational Intelligence and Security, Leshan, China.","DOI":"10.1109\/CIS.2013.106"},{"key":"ref_90","doi-asserted-by":"crossref","first-page":"746","DOI":"10.1109\/TIFS.2015.2509912","article-title":"Conjunctive keyword search with designated tester and timing enabled proxy re-encryption function for e-health clouds","volume":"11","author":"Yang","year":"2015","journal-title":"IEEE Trans. Inf. Forensics Secur."},{"key":"ref_91","doi-asserted-by":"crossref","first-page":"e4211","DOI":"10.1002\/cpe.4211","article-title":"Semantic keyword searchable proxy re-encryption for postquantum secure cloud storage","volume":"29","author":"Yang","year":"2017","journal-title":"Concurr. Comput. Pract. Exp."},{"key":"ref_92","doi-asserted-by":"crossref","unstructured":"Shi, Y., Liu, J., Han, Z., Zheng, Q., Zhang, R., and Qiu, S. (2014). Attribute-based proxy re-encryption with keyword search. PLoS ONE, 9.","DOI":"10.1371\/journal.pone.0116325"},{"key":"ref_93","doi-asserted-by":"crossref","first-page":"2858","DOI":"10.1002\/cpe.3754","article-title":"A restricted proxy re-encryption with keyword search for fine-grained data access control in cloud storage","volume":"28","author":"Chen","year":"2016","journal-title":"Concurr. Comput. Pract. Exp."},{"key":"ref_94","unstructured":"Hong, H., and Sun, Z. (2017, January 28\u201330). Towards secure data sharing in cloud computing using attribute based proxy re-encryption with keyword search. Proceedings of the 2017 IEEE 2nd International Conference on Cloud Computing and Big Data Analysis (ICCCBDA), Chengdu, China."},{"key":"ref_95","doi-asserted-by":"crossref","first-page":"1798","DOI":"10.1587\/transcom.2017EBP3274","article-title":"Attribute-Based Keyword Search with Proxy Re-Encryption in the Cloud","volume":"101","author":"Chen","year":"2018","journal-title":"IEICE Trans. Commun."},{"key":"ref_96","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1109\/TPDS.2012.97","article-title":"Scalable and secure sharing of personal health records in cloud computing using attribute-based encryption","volume":"24","author":"Li","year":"2012","journal-title":"IEEE Trans. Parallel Distrib. Syst."},{"key":"ref_97","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1007\/s10916-014-0178-y","article-title":"Efficient secure-channel free public key encryption with keyword search for EMRs in cloud storage","volume":"39","author":"Guo","year":"2015","journal-title":"J. Med Syst."},{"key":"ref_98","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1007\/s10916-016-0609-z","article-title":"An efficient searchable encryption against keyword guessing attacks for sharable electronic medical records in cloud-based system","volume":"40","author":"Wu","year":"2016","journal-title":"J. Med Syst."},{"key":"ref_99","doi-asserted-by":"crossref","first-page":"3243","DOI":"10.1007\/s00500-015-1699-0","article-title":"Cloud-based electronic health record system supporting fuzzy keyword search","volume":"20","author":"Liu","year":"2016","journal-title":"Soft Comput."},{"key":"ref_100","doi-asserted-by":"crossref","first-page":"285","DOI":"10.1007\/s10586-018-2855-y","article-title":"Efficient searchable public key encryption against keyword guessing attacks for cloud-based EMR systems","volume":"22","author":"Lu","year":"2019","journal-title":"Cluster Comput."},{"key":"ref_101","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1109\/TETC.2013.2273889","article-title":"PaRQ: A privacy-preserving range query scheme over encrypted metering data for smart grid","volume":"1","author":"Wen","year":"2013","journal-title":"IEEE Trans. Emerg. Top. Comput."},{"key":"ref_102","first-page":"3937","article-title":"Emrq: An efficient multi-keyword range query scheme in smart grid auction market","volume":"8","author":"Li","year":"2014","journal-title":"KSII Trans. Int. Inf. Syst."},{"key":"ref_103","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1016\/j.sysarc.2019.07.005","article-title":"An efficient attribute-based online\/offline searchable encryption and its application in cloud-based reliable smart grid","volume":"98","author":"Eltayieb","year":"2019","journal-title":"J. Syst. Archit."},{"key":"ref_104","doi-asserted-by":"crossref","first-page":"435","DOI":"10.1007\/s12243-019-00716-8","article-title":"Certificateless public key encryption with conjunctive keyword search and its application to cloud-based reliable smart grid system","volume":"74","author":"Uwizeye","year":"2019","journal-title":"Ann. Telecommun."},{"key":"ref_105","first-page":"1","article-title":"Public key encryption with keyword search from lattices","volume":"19","author":"Gu","year":"2013","journal-title":"Int. J. Inf. Technol."},{"key":"ref_106","doi-asserted-by":"crossref","unstructured":"Gu, C., Zheng, Y., Kang, F., and Xin, D. (2015). Keyword search over encrypted data in cloud computing from lattices in the standard model. Proceedings of the 2015 Second International Conference on Cloud Computing and Big Data in Asia, Springer.","DOI":"10.1007\/978-3-319-28430-9_25"},{"key":"ref_107","first-page":"425","article-title":"Semantic searchable encryption scheme based on lattice in quantum-era","volume":"32","author":"Yang","year":"2016","journal-title":"J. Inf. Sci. Eng."},{"key":"ref_108","doi-asserted-by":"crossref","first-page":"907","DOI":"10.1007\/s11277-018-5357-6","article-title":"Trapdoor security lattice-based public-key searchable encryption with a designated cloud server","volume":"100","author":"Zhang","year":"2018","journal-title":"Wirel. Pers. Commun."},{"key":"ref_109","doi-asserted-by":"crossref","unstructured":"Tahir, S., and Rajarajan, M. (August, January 30). Privacy-preserving searchable encryption framework for permissioned blockchain networks. Proceedings of the 2018 IEEE International Conference on Internet of Things (iThings) and IEEE Green Computing and Communications (GreenCom) and IEEE Cyber, Physical and Social Computing (CPSCom) and IEEE Smart Data (SmartData), Halifax, NS, Canada.","DOI":"10.1109\/Cybermatics_2018.2018.00272"},{"key":"ref_110","doi-asserted-by":"crossref","unstructured":"Tang, Q. (2019). Towards Blockchain-enabled Searchable Encryption. arXiv.","DOI":"10.1007\/978-3-030-41579-2_28"},{"key":"ref_111","doi-asserted-by":"crossref","first-page":"420","DOI":"10.1016\/j.future.2019.01.018","article-title":"Blockchain based searchable encryption for electronic health record sharing","volume":"95","author":"Chen","year":"2019","journal-title":"Future Gener. Comput. 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