Functional Encryption for Threshold Functions (or, Fuzzy IBE) from Lattices

By Shweta Agrawal, Xavier Boyen, Vinod Vaikuntanathan, Panagiotis Voulgaris and Hoeteck Wee.

In Public Key Cryptography (PKC 2012), volume 7293 of Lecture Notes in Computer Science, pages 280-297. Springer, 2012.


Cryptosystems based on the hardness of lattice problems have recently acquired much importance due to their average-case to worst-case equivalence, their conjectured resistance to quantum cryptanalysis, their ease of implementation and increasing practicality, and, lately, their promising potential as a platform for constructing advanced functionalities. In this work, we construct `Fuzzy' Identity Based Encryption from the hardness of the standard Learning With Errors (LWE) problem. We give CPA and CCA secure variants of our construction, for small and large universes of attributes. All are secure against selective-identity attacks in the standard model. Our construction is made possible by observing certain special properties that secret sharing schemes need to satisfy in order to be useful for Fuzzy IBE. We discuss why further extensions are not as easy as they may seem. As such, ours is among the first examples of advanced-functionality cryptosystem from lattices that goes ``beyond IBE''.


- published paper (PS) (PDF) © Springer-Verlag
- author's version (PS) (PDF)
- preliminary eprint report (#2011/414)
- presentation slides (HTML)


  author = {Shweta Agrawal and Xavier Boyen and Vinod Vaikunthanathan and Panagiotis Voulgaris and Howteck Wee},
  title = {Functional Encryption for Threshold Functions (or, Fuzzy IBE) from Lattices},
  booktitle = {Public Key Cryptography---PKC 2012},
  series = {Lecture Notes in Computer Science},
  volume = {7293},
  pages = {280--297},
  publisher = {Berlin: Springer-Verlag},
  year = {2012},
  note = {Available at \url{}}

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