Privacy-Preserving Trade Chain Detection

Abstract

In this paper, we present a novel multi-party protocol to facilitate the privacy-preserving detection of trade chains in the context of bartering. Our approach is to transform the parties’ private quotes into a flow network such that a minimum-cost flow in this network encodes a set of simultaneously executable trade chains for which the number of parties that can trade is maximized. At the core of our novel protocol is a newly developed privacy-preserving implementation of the cycle canceling algorithm that can be used to solve the minimum cost flow problem on encrypted flow networks.