constraint

A limitation on the function of an identity, role, or privilege. (See: rule-based access control.)

Tutorial: In effect, a constraint is a form of security policy and may be either static or dynamic:

• "Static constraint": A constraint that must be satisfied at the time the policy is defined, and then continues to be satisfied until the constraint is removed.
• "Dynamic constraint": A constraint that may be defined to apply at various times that the identity, role, or other object of the constraint is active in the system.