The power of anonymous veto in public discussion

Abstract

The Dining Cryptographers problem studies how to securely compute the boolean-OR function while preserving the privacy of each input bit. Since its first introduction by Chaum in 1988, it has attracted a number of solutions over the past twenty years. In this paper, we propose an exceptionally efficient solution: Anonymous Veto Network (or AV-net). Our protocol is provably secure under the Decision Diffie-Hellman (DDH) and random oracle assumptions, andis better than past work in the following ways. It provides the strongest protection of each input's privacy against collusion attacks; it requires only two rounds of broadcast, fewer than any other solution; the computational load and bandwidth usage are the least among the available techniques; and the efficiency of our protocol is achieved without relying on any private channels or trusted third parties. Overall, the efficiency of our protocol seems as good as one may hope for. ©Springer-Verlag Berlin Heidelberg 2009.