The mechanism used to implement access control is capability styled Privilege Attribute Certificates. A capability is a piece of access control information that is bound to an initiator and that the initiator presents to the access control enforcer. The capability itself contains all, or almost all, information necessary for the enforcer to decide if a requested access should be permitted or not.
To make access control role-based, the Privilege Attribute Server (PAS) that issues PACs must make use of a role-based security information data-base. As we here mainly want to demonstrate how an application perceives the system, we do not discuss the inner workings of the PAS. However, we envision the security information database to be built using the role framework presented in section 4.2.