[cap-talk] Ambient authority, authentication and authorization

[Karp, Alan H]

Jed wrote:
> 
> And yet ... it seems to me that this very distinction is at the heart 
> of the "ambient authority" model and much that I view as broken about 
> the dominant implementations of access control.
> 
While using IBAC (at least in any practical form) necessarily results in
ambient authorities, ABAC systems can exhibit this flaw as well.  That's
what happened to Client Utility.  Due to a mistake on my part, we made
it easy for people to include large bundles of authority with each
request.  Similarly, certificate based ABAC systems allow including
large bundles of authorities.  Even so, ABAC systems are superior to
IBAC in terms of distributed identity management and delegation.

_________________________
Alan Karp
Principal Scientist
Virus Safe Computing Initiative
Hewlett-Packard Laboratories 
1501 Page Mill Road
Palo Alto, CA 94304
(650) 857-3967, fax (650) 857-7029
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