4
$\begingroup$

Am trying to understand Garbled Circuit based approach for Secure Two party Computation. There isn't much leakage in the classic millionaire's problem where the comparison circuit is used.

But imagine they want to do some arithmetic operation (like addition or multiplication) without revealing their individual wealth.

Then although each of them need not reveal their individual wealth using Garbled Circuits approach (by running the protocol with an addition circuit), the sum total of their wealth would easily reveal the other millionaire's wealth (By doing simple difference of the total wealth and self wealth)

So is secure two party computation recommended only for a class of circuits ?

Improve this question
$\endgroup$

1 Answer 1

Reset to default
5
$\begingroup$

Secure multiparty computation guarantees the nothing whatsoever is revealed by the process of computation. It does not say anything about the function. As you correctly point out, there are some functions that reveal a lot and shouldn't be computed, but this analysis is quite out of the scope of secure computation. The question of whether it's "recommended" depends on the application and the choices you may or may not have. You may, for example, want to use secure computation to compute a differentially private version of the function.

Improve this answer
$\endgroup$
3
  • $\begingroup$ Nice it did not occur to me that we can compute a \emph{differentially private} version of the function. Thanks for this insight ! $\endgroup$
    – sashank
    Commented Sep 13, 2015 at 1:31
  • $\begingroup$ Is there any work which discusses on secure computation of differentially private function? I haven't found any differential privacy paper which discusses on this aspect of secure computation. $\endgroup$
    – sun
    Commented Jul 2, 2016 at 4:42
  • $\begingroup$ There is only one paper that I know about: cs.bgu.ac.il/~beimel/Papers/BNO.pdf. $\endgroup$
    – Yehuda Lindell
    Commented Jul 2, 2016 at 18:41

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.