Implementing Gentry's Fully-Homomorphic Encryption Scheme

  title={Implementing Gentry's Fully-Homomorphic Encryption Scheme},
  author={Craig Gentry and Shai Halevi},
  booktitle={International Conference on the Theory and Application of Cryptographic Techniques},
  • Craig GentryS. Halevi
  • Published in
    International Conference on…
    15 May 2011
  • Computer Science, Mathematics
We describe a working implementation of a variant of Gentry's fully homomorphic encryption scheme (STOC 2009), similar to the variant used in an earlier implementation effort by Smart and Vercauteren (PKC 2010. [] Key MethodOur main optimization is a key-generation method for the underlying somewhat homomorphic encryption, that does not require full polynomial inversion.

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Practical Bootstrapping in Quasilinear Time

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It appears likely that there exist encryption functions which permit encrypted data to be operated on without preliminary decryption of the operands, for many sets of interesting operations.

On the sparse subset sum problem from Gentry-Halevi's implementation of fully homomorphic encryption

  • M. Lee
  • Computer Science, Mathematics
    IACR Cryptol. ePrint Arch.
  • 2011
The experiment shows that even their large instance of a sparse subset sum problem could be solved within two days with probability of about 44% and a more conservative parameter choice can easily avoid the attack.