An Efficient E2E Crowd Verifiable E-Voting System

Electronic-voting(e-voting), compared with paper voting, has advantages in several aspects. Among those benefits, the ability to audit the electoral process at every stage is one of the most desired features. In Eurocrypt2015, Kiayias et al. proposed an E2E verifiable e-voting system which first provides E2E verifiability without relying on external sources of randomness or the random oracle model. The main advantage of the system is that election auditors need only the election transcript and the feedback from the voters to pronounce the election process unequivocally valid. Unfortunately, their system comes with a huge performance and storage penalty for the election authority (EA) compared to other e-voting systems such as Helios. The reason is the EA forms the proof of tally results. It is required to precompute several ciphertexts. The performance penalty on the EA appears to be intrinsic: voters cannot compute an enciphered ballot themselves because it seems unprovable. In this work, we construct a new e-voting system that retains strong E2E characteristics while eliminating the performance and storage penalty of the EA. Our construction is practical and has a similar performance to Helios. The privacy of our construction relies on the SXDH assumption over bilinear groups via complexity leveraging.