Multi-Party Computation for Inclusivity in Decentralised Identity Management

Typical DI and SSI systems have only three roles: issuer, verifier, and user (data owner). However, this may not be practical in the real-world where not all individuals can be entrusted to self-manage their identities and decide when and with whom to share which data [1]. Additionally, a sophisticated and demanding key management system is disadvantageous to various social groups such as the elderly and disabled [2]. Therefore, there should be a mechanism to relay the control over one's identity data to a trusted party (\textit{e.g.}, a parent), based on some external factors (e.g., a medical condition). So far, only one system (Sovrin) has the concept of a “guardian”, that addresses this issue by “handling an identity on behalf of a vulnerable person or anyone else incapable of managing their digital wallet” [3]. However, there is no detailed discussion on how this is technically achieved and why it is compliant with SSI principles. QuarkID framework recognizes this challenge in their whitepaper [4]. However, the only relevant document QuarkID refers to is the Sovrin Foundation's concept of guardianship.

This thesis will explore the design and implementation of a guardian component within SSI systems to support vulnerable users (e.g., elderly, disabled) who may struggle with self-managing their digital identities. The research will investigate Multi-Party Computation (MPC) as a potential solution for delegating identity management to trusted parties while maintaining compliance with SSI principles. The thesis will also evaluate the feasibility, costs, and performance of the guardian component.

Sources to Consider: 

[1]  L. Weigl, T. Barbereau, A. Rieger, G. Fridgen, “The Social Construction of Self-Sovereign Identity: An Extended Model of Interpretive Flexibility”, Proceedings of the 55th Hawaii International Conference on System Sciences, HICSS, 2022. URL: http://hdl.handle.net/10125/79649.

[2] M. Cheesman, “Self-Sovereignty for Refugees? The Contested Horizons of Digital Identity”, Geopolitics 27 (2022) 134–159. DOI: 10.1080/14650045.2020.1823836. 

[3] M. Shuaib, N. H. Hassan, S. Usman, S. Alam, S. Bhatia, A. Mashat, A. Kumar, M. Kumar, “Self-Sovereign Identity Solution for Blockchain-Based Land Registry System: A Comparison”, Mobile Information Systems 2022 (2022) e8930472. Publisher: Hindawi. DOI: 10.1155/2022/8930472. 

[4] QuarkID, “Quark id whitepaper: Self-sovereign identity: Basis of a new decentralized digital ecosystem”, n.d. URL: https://github.com/gcba/WhitePaper/tree/master.