FLEXIBLE PROOF-OF-WORK: A DECENTRALIZED UNPREDICTABLE NUMBER GENERATOR

Abstract

We propose a new proof-of-work protocol called “Flexible Proof-of-Work” to generate an unpredictable set of numbers. This can be seen as a component of a general framework for a decentralized random number generator. The algorithm ensures experimentally that the result is feasible and unpredictable. Moreover we demonstrate that the algorithm can be easily implemented on Ethereum blockchain system by smart contracts, and miners who have limited resource are still able to compute solutions. Meanwhile during the process, the problems are changing continuously by taking new solutions into account, making an adversary hard to attack the protocol by pre-calculating the final results.