Unconditionally secure electronic voting

Abstract

In this chapter, we will show how to achieve unconditional or information-theoretic security in electronic voting with the following property: 1. Even all voters and tallying authorities have unbounded computing power, the distorted integrity of the voting results can be detected and proved incorrect by every honest voter, 2. If at least one tallying authority is honest, then the privacy of the ballots are protected everlastingly even the other voters and tallying authorities are malicious and have the unbounded computing power. We assume single trusted authority who honestly delivers a particular form of secret key to every voter and tallying authority. This authority can be destroyed before the election is started. Two information-theoretic primitives are introduced based on this pre-distributed secret key, unconditionally secure oblivious polynomial evaluation (US-OPE) and unconditionally secure publicly verifiable secret sharing (US-PVSS). These primitives make the election process unconditionally secure in the above sense and efficient. The resulting scheme requires in a case of 1 million voters, the storage complexity to store private key required for each voter is 300MB. Communication complexity to verify the whole tallying process (the heaviest part) is 27GB in a case of tolerating up to 1000 colluding users, and 220GB in a case of tolerating up to 10,000 colluders. © 2010 Springer-Verlag.