[cap-talk] Reasoning about dynamic vs. static (was: POLA: what about dynamics?)

[Jonathan S. Shapiro]

On Mon, 2007-10-01 at 14:28 -0700, Jed Donnelley wrote:

> I want to at least make clear my belief that it isn't
> dynamic delegation of permissions that makes reasoning
> about security more difficult but rather just the existence
> of communication channels that makes such reasoning more
> difficult.

I agree. This insight was formalized in Bishop and Snyder's paper "The
Transfer of Information and Authority in a Protection System", which
introduced the distinction between de jure and de facto authority. The
key point is that it doesn't matter which one you have.
-- 
Jonathan S. Shapiro
Managing Director
The EROS Group, LLC
www.coyotos.org, www.eros-os.org