A Publicly-Verifiable Mix-Net with Everlasting Privacy Towards Observers
In this paper, the authors present a novel, publicly verifiable mixing scheme which has everlasting privacy towards observers: all the information published on the bulletin board by the mixes (audit information etc) reveals no information about the identity of any of the messages published. The correctness of the mixing process is statistical: even if all authorities conspire, they cannot change the contents of any message without being detected with overwhelming probability. They accomplish this by encoding the messages submitted using so-called Pedersen commitments. Decoding (opening) these is possible because they create a parallel mix-net run by the same mixes to which the public has no access.