Private Computations Over the Integers (extended abstract )

The subject of this work is the possibility of private distributed computations of nargument functions defined over the integers. A function f is t - private if there exists a protocol for computing f, so that no coalition of 5 t participants can infer any additional information from the execution of the protocol. It is known that over finite domains, every function can be computed - prieven n - private. We prove that this result cannot be extended to infinite domains. The possibility of privately computing f is shown to be closely related to the communication complexity of f. Using this relation, we show, for example, that n - argument addition is 191 - private