Ben Miller at Government Technology: “Hash chains are not a new concept in cryptography. They are, essentially, a long chain of data connected by values called hashes that prove the connection of each part to the next. By stringing all these pieces together and representing them in small values, then, one can represent a large amount of information without doing much. Josh Benaloh, a senior cryptographer for Microsoft Research and director of the International Association for Cryptologic Research, gives the rough analogy of taking a picture of a person, then taking another picture of that person holding the first picture, and so on. Loss of resolution aside, each picture would contain all the images from the previous pictures.
It’s only recently that people have found a way to extend the idea to commonplace applications. That happened with the advent of bitcoin, a digital “cryptocurrency” that has attained real-world value and become a popular exchange medium for ransomware attacks. The bitcoin community operates using a specific type of hash chain called a blockchain. It works by asking a group of users to solve complex problems as a sort of proof that bitcoin transactions took place, in exchange for a reward.
“Academics who have been looking at this for years, when they saw bitcoin, they said, ‘This can’t work, this has too many problems,’” Benaloh said. “It surprised everybody that this seems to work and to hold.”
But the blockchain concept is by no means limited to money. It’s simply a public ledger, a bulletin board meant to ensure accuracy based on the fact that everyone can see it — and what’s been done to it — at all times. It could be used to keep property records, or to provide an audit trail for how a product got from factory to buyer.
Or perhaps it could be used to prove the veracity and accuracy of digital votes in an election.
It is a potential solution to the problem of cybersecurity in online elections because the foundation of blockchain is the audit trail: If anybody tampered with votes, it would be easy to see and prove.
And in fact, blockchain elections have already been run in the U.S. — just not in the big leagues. Voatz, a Massachusetts-based startup that has struck up a partnership with one of the few companies in the country that actually builds voting systems, has used a blockchain paradigm to run elections for colleges, school boards, unions and other nonprofit and quasi-governmental groups. Perhaps its most high-profile endeavor was authenticating delegate badges at the 2016 Massachusetts Democratic Convention….
Rivest and Benaloh both talk about another online voting solution with much more enthusiasm. And much in the spirit of academia, the technology’s name is pragmatic rather than sleek and buzzworthy: end-to-end verifiable Internet voting (E2E-VIV).
It’s not too far off from blockchain in spirit, but it relies on a centralized approach instead of a decentralized one. Votes are sent from remote electronic devices to the election authority, most likely the secretary of state for the state the person is voting in, and posted online in an encrypted format. The person voting can use her decryption key to check that her vote was recorded accurately.
But there are no validating peers, no chain of blocks stretching back to the first vote….(More)”.