Proof of Personhood
Source
* Article: Proof-of-Personhood: Redemocratizing Permissionless Cryptocurrencies. By Maria Borge, Eleftherios Kokoris-Kogia et al. EPFL, 2018
"Permissionless blockchain-based cryptocurrenciescommonly use proof-of-work (PoW) or proof-of-stake (PoS) toensure their security, e.g. to prevent double spending attacks.However, both approaches have disadvantages: PoW leads tomassive amounts of wasted electricity and re-centralization,whereas major stakeholders in PoS might be able to create amonopoly. In this work, we propose proof-of-personhood (PoP),a mechanism that binds physical entities to virtual identities ina way that enables accountability while preserving anonymity.Afterwards we introduce PoPCoin, a new cryptocurrency,whose consensus mechanism leverages PoP to eliminate the dis-advantages of PoW and PoS while ensuring security. PoPCoinleads to a continuously fair and democratic wealth creationprocess which paves the way for an experimental basic incomeinfrastructure."