A FRAMEWORK TO INTEGRATION TRUST INTO USAGE CONTROL

Overview of UCON

The UCON model proposed by Park and Sandhu (2004) is a generalization of access control to cover authorization, obligation, conditions, continuity (ongoing controls), and mutability. Authorization handles decisions on user accesses to target resources. Obligations are the mandatory requirements for a subject before or during a usage exercise. Conditions are subject, object, environmental, or system requirements that have to be satisfied before granting of accesses. Subject and object attributes can be mutable. Mutable attributes can be changed because of accesses, whereas immutable attributes can be changed only by administrative actions.

Trust Evaluation

For every request, the owner of resources assigns a trust value within [0, 1] to the requester. The trust is evaluated based on history observations and peer recommendations from referees. The history-based observations are the previous interactions the owner had with the requester. The peer recommendations may include signed trust-assertions from other principals, or a list of referees whom the owner can contact for recommendations.