Proof of human engagement on decentralized networks

Abstract

We present an approach to proving human engagement on decentralized networks, such as blockchains. Our approach is capable of differentiating real human users from computer bots with high probabilities. In our framework, computer users occasionally need to solve CAPTCHA-like tasks to prove that they are real humans. Our protocol is attack-resistant and prevents computer bots from fetching answers posted by other users during the answer collection period. The consensual answer for a task is defined as the majority vote with stakes weighted. Our experimental simulation on the Steem blockchain shows that the proof-of-human-engagement consensus can be reached with a probability above 99% when 15% stake-weighted users are computer bots.