Aimed at a 'real' problem of preventing conflicts of interest
Golden Rule = There must be no flow of
information that causes a conflict of interest.
Simple security (ss) property:
A subject may only be granted
access to an object if:
the object is in the same company dataset
as an object already accessed by the subject
the object does not belong to any of the
conflict of interest classes of objects
already accessed by the subject
deals with direct information flow
Star property
deals with indirect flow
A subject s is permitted write access to an object
only if s has no read access to any object o', which
is in a different company dataset and is unsanitised
One of the implications of the *-property is that access rights
of subjects change dynamically with every access operation.
You need to understand and appreciate how a different type of
security policy can be described in terms of a security model.