#codingexercise
Double GetAlternateEvenNumberRangecubeRtProductSquares()(Double [] A)
{
if (A == null) return 0;
Return A.AlternateEvenNumberRangecubeRtProductSquares();
}
Today we continue the discussion on Access Control.  We alluded to how RBAC does not adequately address a grid computing environment.  We now look at a few specific models of RBAC.
IRBAC2000 was proposed by Kapadia. Its called a role-based multi domain mutual operation model. By the dynamic mapping of roles among domains, it can solve the mutual operation between two reciprocal domains to  some extent. Roles are mapped to the corresponding local system definitions.  The mapping is dynamic and this provides flexibility.  The shortcoming is that once the mapping is done, access cannot be restricted further because it could violate the mutually exclusive roles. Say if it got mapped to one role and then we added another mutually exclusive role to the same external access, then our system would be confused.
The MDRBAC was introduced to solve this specific problem. It introduces notions such as domain agency, role mapping with time attribute, and minimized role mapping  restriction and it is applied in the access control among reciprocal domains.
The time attribute is helpful to restrict the duration for the mapping is made so that the mappings can be renewed with another or refreshed.
#codingexercise
Double GetAlternateEvenNumberRangecubeRtProduct()(Double [] A)
{
if (A == null) return 0;
Return A.AlternateEvenNumberRangecubeRtProduct();
}