PEPR '25: 2025 USENIX Conference on Privacy Engineering Practice and Respect

Tanusree Sharma, Pennsylvania State University


With the rise of AI-powered deception, identity verification systems are increasingly important to distinguish between AI and humans. Building on related concepts, like, decentralized identifiers (DIDs), proof-of-personhood, anonymous credentials, personhood credentials (PHCs) emerged as an alternative approach, enabling individuals to verify that they are a unique person without disclosing additional information. However, new technologies might introduce some friction due to users' misunderstandings and mismatched expectations. This talk will discuss how people reason about unknown privacy and security guarantees of PHCs compared to current methods; and factors that influence how people would like to manage PHCs. Specifically, it will address critical design considerations, including the role of trusted issuers (e.g., government, private entities), the reliability of data attributes used for credential issuance (e.g., biometrics, physical IDs, selfies), and the trade-offs between centralized and decentralized issuance systems.


https://www.usenix.org/conference/pepr25/presentation/sharma