Belenios: A Simple Private and Verifiable Electronic Voting System

Abstract

We present the electronic voting protocol Belenios together with its associated voting platform. Belenios guarantees vote privacy and full verifiability, even against a compromised voting server. While the core of the voting protocol was already described and formally proved secure, we detail here the complete voting system from the setup to the tally and the recovery procedures. We comment on the use of Belenios in practice. In particular, we discuss the security choices made by election administrators w.r.t. the decryption key and the delegation of some setup tasks to the voting platform.

A Transparent Referendum Protocol with Immutable Proceedings and Verifiable Outcome for Trustless Networks

“…Therefore participants do not obtain the same level of communicative transparency as in our solution. [Cortier et al, 2019] rely on a threshold system that can defend the secrecy of ballots until a fixed number of colluding adversaries. However their protocol provides no control mechanism to monitor whether such collusion was attempted or has already occurred.…”

Provably Improving Election Verifiability in Belenios

“…Belenios extends Helios in order to get stronger election verifiability [2,16]. There is no single party that has to be trusted: verifiability holds as soon as either the voting server or the voting registrar is not corrupted.…”

Privacy-oriented cryptographic primitives and protocols for electronic voting

“…The existence of an independent RA changes the trust assumptions and leads to two variations of verifiability which will be explored in the following sections. A system that bears many similarities to Helios with credentials is Belenios [CGG19]. Another variation of Helios to add eligibility verifiability is proposed in [Sri+14].…”

“…check that there is no identical copy of the ballot ciphertext). In voting systems with RAs, such as Helios-C [Cor+14] or Belenios [CGG19], it can additionally validate the credentials of the voters. In these cases.…”

“…Another game-based definition of receipt-freeness was defined for the BeleniosRF voting scheme [Cha+16]. This recent scheme adds receipt-freeness to the Belenios voting scheme [CGG19], a variation of Helios-C [Cor+14], where each voter is assumed to have a private key to sign the ballot. BeleniosRF uses the cryptographic primitive of signatures on rerandomizable ciphertexts proposed in [Bla+11].…”