A Self-Sovereign Identity Approach to Decentralized Access Control with Transitive Delegations

In this paper, we introduce a new decentralized access control framework with transitive delegation capabilities that tackles the performance and scalability limitations of the existing state-of-the-art solutions. In order to accomplish this, the proposed solution is anchored in the self-sovereign identity (SSI) paradigm, which embodies a distributed identity management system. By adopting this paradigm, we obviate slow cryptographic premises such as identity-based encryption (IBE) that were used in prior work. Furthermore, we enhance the existing verifiable credentials (VCs) from this paradigm by introducing our own decentralized permission objects to support the concept of transitive delegations. This concept allows delegates to further delegate their access to resources with the same or fewer privileges to other entities within the framework. This renders our solution suitable for diverse scenarios, including applications in decentralized building access management. To the best of our knowledge, we are the first to introduce the concept of transitive delegations in this paradigm. Finally, our performance experiments show a performance enhancement of three orders of magnitude compared to the prevailing state-of-the-art solutions.