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Efficient Secure-Channel Free Public Key Encryption with Keyword Search for EMRs in Cloud Storage


Searchable encryption is an important cryptographic primitive that enables privacy-preserving keyword search on encrypted electronic medical records (EMRs) in cloud storage. Efficiency of such searchable encryption in a medical cloud storage system is very crucial as it involves client platforms such as smartphones or tablets that only have constrained computing power and resources. In this paper, we propose an efficient secure-channel free public key encryption with keyword search (SCF-PEKS) scheme that is proven secure in the standard model. We show that our SCF-PEKS scheme is not only secure against chosen keyword and ciphertext attacks (IND-SCF-CKCA), but also secure against keyword guessing attacks (IND-KGA). Furthermore, our proposed scheme is more efficient than other recent SCF-PEKS schemes in the literature.

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The authors would like to thank anonymous reviewers for their useful comments. We also thank Syh-Yuan Tan (Multimedia University) for his helpful discussions on Java implementation of the proposed scheme. L. Guo is supported by the National Science Foundation of China under Grant No. 61202365 and Technology Foundation for Selected Overseas Chinese Scholar, Department of Human Resources and Social Security of Shanxi Province. W.-C. Yau is partially supported by FRGS Grant (FRGS/1/2012/TK06/MMU/03/9).

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Correspondence to Wei-Chuen Yau.

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This article is part of the Topical Collection on Systems-Level Quality Improvement.

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Guo, L., Yau, WC. Efficient Secure-Channel Free Public Key Encryption with Keyword Search for EMRs in Cloud Storage. J Med Syst 39, 11 (2015).

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  • Electronic medical record
  • Cloud storage
  • Public key encryption
  • Keyword search
  • Keyword guessing attack
  • Standard model