Multi-user Searchable Encryption in the Cloud

  • Cédric Van RompayEmail author
  • Refik Molva
  • Melek Önen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9290)


While Searchable Encryption (SE) has been widely studied, adapting it to the multi-user setting whereby many users can upload secret files or documents and delegate search operations to multiple other users still remains an interesting problem. In this paper we show that the adversarial models used in existing multi-user searchable encryption solutions are not realistic as they implicitly require that the cloud service provider cannot collude with some users. We then propose a stronger adversarial model, and propose a construction which is both practical and provably secure in this new model. The new solution combines the use of bilinear pairings with private information retrieval and introduces a new, non trusted entity called “proxy” to transform each user’s search query into one instance per targeted file or document.


Hash Function Cloud Service Provider Trusted Third Party Privacy Requirement Adversary Model 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors thank the anonymous reviewers for their suggestions for improving this paper.

 This work was partially funded by the FP7-USERCENTRICNETWORKING european ICT project (grant 611001).


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.EURECOMSophia AntipolisFrance

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