dRBAC: distributed role-based access control for dynamic coalition environments

distributed role-based access control (dRBAC) is a scalable, decentralized trust-management and access-control mechanism for systems that span multiple administrative domains. dRBAC utilizes PKI identities to define trust domains, roles to define controlled activities, and role delegation across domains to represent permissions to these activities. The mapping of controlled actions to roles enables their namespaces to serve as policy roots. dRBAC distinguishes itself from previous approaches by providing three features: (1) third-party delegation of roles from outside a domain's namespace, relying upon an explicit delegation of assignment; (2) modulation of transferred permissions using scalar valued attributes associated with roles; and (3) continuous monitoring of trust relationships over long-lived interactions. The paper describes the dRBAC model and its scalable implementation using a graph approach to credential discovery and validation.