ALGORAND: The Efficient and Democratic Ledger.

Abstract

Algorand is a truly decentralized, new, and secure way to manage a shared ledger. Unlike prior approaches based on {\em proof of work}, it requires a negligible amount of computation, and generates a transaction history that does not fork with overwhelmingly high probability. This approach cryptographically selects ---in a way that is provably immune from manipulations, unpredictable until the last minute, but ultimately universally clear--- a set of verifiers in charge of constructing a block of valid transactions. This approach applies to any way of implementing a shared ledger via a tamper-proof sequence of blocks, including traditional blockchains. This paper also presents more efficient alternatives to blockchains, which may be of independent interest. Algorand significantly enhances all applications based on a public ledger: payments, smart contracts, stock settlement, etc. But, for concreteness, we shall describe it only as a money platform.