Eden: An Edge Computing Empowered Proof-of-Personhood Protocol for Anti-Sybil in Blockchain-based Metaverse

The blockchain-based metaverse has achieved great success through decentralized ownership of digital assets. However, the prevalence of Sybil attacks seriously threatens the security of assets, where attackers create multiple fake wallets to gain illegal benefits from metaverse activities such as token airdrops. Existing anti-Sybil mechanisms either rely on expensive specialised biometric devices or use imprecise empirical analysis of historical transaction behaviour, both of which are less effective in the metaverse. This paper presents the Eden protocol, a novel proof-of-personhood protocol designed to counter Sybil attacks in the metaverse. The Eden protocol uses a hybrid approach that combines edge computing-based personhood video recognition with on-chain transactional activity analysis to ensure a unique link between a user in the physical world and a wallet address. To make the Eden protocol trustworthy, we also introduce a consensus mechanism, Proof-of-Trustworthiness. It aggregates the above procedures into a personhood score to reflect the personhood of a wallet in a decentralized way. We develop prototypes of Eden devices based on low-cost generic hardware together with a metaverse campus that provides avatars with trustworthy identities. Intensive performance evaluation and security analysis show that the Eden protocol is practical for anti-sybil in blockchain-based metaverse scenarios.