  Electing democratic representatives via voting has been a common mechanism
since the 17th century. However, these mechanisms raise concerns about
fairness, privacy, vote concealment, fair calculations of tally, and proxies
voting on their behalf for the voters. Ballot voting, and in recent times,
electronic voting via electronic voting machines (EVMs) improves fairness by
relying on centralized trust. Homomorphic encryption-based voting protocols
also assure fairness but cannot scale to large scale elections such as
presidential elections. In this paper, we leverage the blockchain technology of
distributing trust to propose a smart contract-based protocol, namely, \proto.
There are many existing protocols for voting using smart contracts. We observe
that these either are not scalable or leak the vote tally during the voting
stage, i.e., do not provide vote concealment. In contrast, we show that FASTEN
preserves voter's privacy ensures vote concealment, immutability, and avoids
double voting. We prove that the probability of privacy breaches is negligibly
small. Further, our cost analysis of executing FASTEN over Ethereum is
comparable to most of the existing cost of elections.
