Proof-of-CAPTCHA: A True ASIC-Resistant Consensus

Abstract: In Proof-of-Work (PoW) based blockchain systems, rewards received by miners are proportional to the computation power under their control, hence they are incentivized to use powerful hardware such as ASIC. This prevents commodity computers from joining the network and keeping the system decentralized, and leads to widespread waste of computation power and electrical energy for personal benefit. In this paper, we propose a new consensus algorithm named Proof-of-CAPTCHAs (PoCA), which employs CAPTCHAs upon completion of each block computation in order to achieve an ASIC-resistant nature while preserving user anonymity. Keywords: Blockchain, Cryptocurrency, ASIC-Resistant, Proof-of-CAPTCHA