ensuring voter privacy and anonymity is of utmost importance for any democratic voting system. With online voting, there are additional technical challenges to guarantee these principles compared to traditional in-person voting. Through a careful systems design that leverages modern cryptography techniques, it is certainly possible to build an online voting system that protects voter privacy as effectively as or even better than existing paper-based methods.

Some of the key measures such an online voting system would need to incorporate include:

Using homomorphic encryption for votes: The votes cast by each voter would be encrypted using a homomorphic encryption scheme before being recorded in the system. Homomorphic encryption allows for mathematical operations to be performed on the encrypted votes without decrypting them first. This ensures the vote values themselves are not revealed to anyone including the system administrators and attackers. Only the final aggregated election results would need to be decrypted at the end to be read in clear text.

Separating voter identification from vote contents: The system would separate the process of verifying a voter’s identity and eligibility to cast a ballot from the recording of actual vote contents. During identification, the voter would authenticate using mechanisms like digital signatures or multi-factor authentication without revealing how they voted. The vote would be linked to the voter through an anonymized token or cryptographic commitment instead of directly associating the two.

Implementing a private bulletin board: The encrypted votes would be posted on a distributed “bulletin board” stored across multiple independent nodes. This prevents any single point of failure or single party from accessing all votes. The bulletin board would also hide the link between votes and voter identities using techniques like mix-nets, zero-knowledge proofs etc. to achieve unconditionalsender and recipient anonymity.

Allowing verifiable receipts without vote selling: Voters could be given anonymized receipts to later verify their votes were properly counted, but the receipts would not reveal which candidates were selected. This assures voters their votes prevailed while preventing them from using receipts to “sell” their votes. Advanced crypto like blind signatures or mix-nets could be leveraged to achieve this.

Enforcing message integrity using digital signatures: Each message exchanged during voting – login request, votes, receipts etc. would be digitally signed by the concerned entities like voters and authorities. This ensures messages are not tampered with or replayed. The signatures would again be anonymized to not reveal identities.

Conducting compulsory audits and risk-limiting audits: The system code and cryptography would need to undergo security evaluations and formal verification. Regular audits of ballot manifests, voter rolls and tallying procedures should be carried out by independent auditors. Statistical auditing methods like risk-limiting audits could also be employed to check tallies against a random sample of original votes.

Deploying the system on open-source software running on tamper-proof hardware: Placing strict controls on system software and infrastructure can boost security. Running vote collection and counting modules only on dedicated hardware platforms incorporated with trusted platform modules helps ensure code and data integrity. Independent security assessments of all components should also be conducted periodically.

By building in advanced privacy-enhancing techniques like homomorphic encryption, zero-knowledge proofs, mix-nets and cryptographic commitments right from the design phase, incorporating open verification procedures as well as subjecting the system to mandatory validation audits – it is completely possible to create an online voting infrastructure that protects voter anonymity and ballots to at least the same degree as existing paper-based methods if not better. Proper implementation of information security best practices along with the latest advances in cryptography research could deliver a verifiably confidential and verifiable online voting solution.