Access Control using Blockchain: A Taxonomy and Review

After the introduction of blockchain as a cryptocurrency platform, researchers and industry leaders have come up with novel ways of utilizing the technology. One emerging use case for blockchain is access control, since it solves the problem of trust deficit while being distributed, auditable and private. This paper lists various access control models that have been proposed or implemented on blockchain platforms. It also provides an analysis of the performance of some of these models. Analysis shows that access control models are progressing from the traditional identity-based systems to role/attribute-based systems with observed structural shifts from centralized to decentralized. Key benefits of blockchain-based access control systems noted are improved transparency over access control and logging; improved, more complex policy management; and the possibility to implement access controls in trust-less systems.