Secure Computations on Non-Integer Values
In this paper the authors present for the first time a framework that allows secure two-party computations on approximations of real valued signals. In the solution, they use a quantized logarithmic representation of the signal samples, which enables to represent both very small and very large numbers with bounded relative error. They show that numbers represented in this way can be encrypted using standard homomorphic encryption schemes; furthermore they give protocols that allow to perform all arithmetic operations on such encrypted values. Finally they demonstrate the practicality of the framework by applying it to the problem of filtering encrypted signals.