Department of Mathematics and Computing Seminars

Delegation models based on role-based access control management have been known as flexible and efficient access management for data sharing on distributed environment. Delegation revocations are a significant functionality for the models in distributed environment when the delegated roles or permissions are required to get back. However, problems may arise in the revocation process when one user delegates user $U$ a role and another user delegates a negative authorization of the role.

This paper aims to analyse various role-based delegation revocation features through examples. Revocations are categorized in four dimensions: Dependency, Resilience, Propagation and Dominance. According the dimensions, sixteen types of revocations exist for specific requests in access management. We present revocation delegating models, and then discuss user delegation authorization and the impact of revocation operations. Finally, comparisons with other related work are indicated.