A pervasively verifiable online voting scheme

We present an improvement of Ohkubo et al.’s e-voting protocol [OMA99]: We provide that the validator’s signature is attached directly to the vote although the vote has been encrypted before. Thus verifiability does not end before tallying like in the original scheme but is pervasive even beyond the end of the election. This prevents manipulation of the plaintext votes and offers verifiability to the public instead of restricting it to the talliers. Moreover, privacy can be ensured without using blind signatures, which facilitates receipt-freeness. Our variant of the scheme also allows the voter to seemingly comply with the demand of a coercer while actually casting the vote she intended.