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Overview
Project Partners
Prototype
Logic
Presentations
Common Policies
Related Links
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The Logic
The logic is a fragment of the one suggested by Joseph Y. Halpern, Ron van der Meyden and Fred B. Schneider in "Less is More: Logical Foundations for Trust Management". This logic was chosen, because it strikes a nice balance between simplicity and expressibility.
My logic has:
- a built-in predicate Permitted. Permitted(i, a, t) means that individual i is permitted to do action a at time t.
- pre-defined sorts
- a sort of principals corresponding to active entities in the system.
- a sort of actions.
- a sort of times.
- a policy is a first-order formula of the form:
forall x_1, ..x_n (f=>g) where
- f is quantifier-free
- g is the permitted predicate or its negation.
Sample Policies Written in the Logic
Questions concerning this project should be sent to
Vicky Weissman.
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