Sybil Attacks and Defenses

This lecture covers the concept of Sybil attacks in the context of weak internet identities, where one user can create multiple accounts to gain control. The instructor discusses various defense mechanisms such as cost-centric and human-centric approaches, including the use of smart contracts for staking and slashing. Additionally, the lecture explores the importance of strong identity checking, verifiable identity proxies, and reputation-based defenses. The instructor also delves into trust-network approaches and biometric identity systems like Aadhaar, emphasizing the need for presence-based verification and pseudonymous parties.