[xacml] New issue#3 from "Boolean Policy resolution"

[Anne Anderson <Anne.Anderson@Sun.com>]

PM-7-?: How can the set of combinators be extended?

We agreed at the March, 2002 F2F that XACML would define the
<AND>, <OR>, <NOT>, <N-OF>, and <ORDERED-[AND|OR|NOT|N-OF]>
combinators.  How can a policy writer extend this set to define a
new combinator, such as BEST-MATCH-OR?

Potential Resolution:

The set of Combinators may be extended by specifying a name
for the new Combinator, a URI that is associated with the
semantics of the new Combinator, and a type that specifies
the way the URI is to be interpreted.  Not all XACML PDPs
will be able to interpret all extensions, but any PDP that
can handle the specified type and can access the specified
URI can handle the specified extended Combinator.

An example of a possible extended Combinator is
BEST-MATCH-OR.  The type for such an extended Combinator
might be "JavaClass".  The URI for each might point to a Java
class that takes a set of Predicates as input and implements
the semantics of the combinator to return a result of TRUE,
FALSE, NOT-APPLICABLE, or ERROR.]

Champion: Anne
-- 
Anne H. Anderson             Email: Anne.Anderson@Sun.COM
Sun Microsystems Laboratories
1 Network Drive,UBUR02-311     Tel: 781/442-0928
Burlington, MA 01803-0902 USA  Fax: 781/442-1692