Date Added: Aug 2010
Delegation is a widely used and widely studied mechanism in access control systems. Delegation enables an authorized entity to nominate another entity as its authorized proxy for the purposes of access control. Existing delegation mechanisms tend to rely on manual processes initiated by end-users. The authors believe that systems in which the set of available, authorized entities fluctuates considerably and unpredictably over time require delegation mechanisms that can respond automatically to the absence of appropriately authorized users.