Permissionless Blockchain-Based Sybil-Resistant Self-Sovereign Identity Utilizing Attested Execution Secure Processors
Koichi Moriyama, Akira Otsuka · 2022
The current circumstance that requires people more online has encouraged us to address digital identity preserving privacy. There is a momentum of research addressing Self-Sovereign Identity (SSI); many research approach blockchain technology as a foundation. SSI brings natural persons various benefits such as their owning controls; on the other side, digital identity systems in the real world require Sybil-resistance to comply with Anti-Money-Laundering (AML) and other needs. Our proposal in this paper is to build a secure SSI system by utilizing permissionless blockchain and Rafael Pass et al.'s contribution of the formal abstraction of Attested Execution Secure Processors (AESPs). Our proposal of the AESP-based SSI architecture and system protocols, ∏Gatt, demonstrates the powerfulness of hardware-assisted security and the formal abstraction of AESPs, fitting into building a proper SSI system that satisfies Sybil-resistance. Assuming AESPs and Gatt, the protocols may eliminate the online distributed committee assumed in other research such as CanDID; thus, ∏Gattallows not to rely on multiparty computation (MPC), and it brings drastic flexibility and efficiency compared with the existing SSI systems.