Re: [xacml-users] Rationale for 3.0 schema combining policy and contextschemas in same file and namespace

[Erik Rissanen <erik@axiomatics.com>]

One of the 2.0 schemas imported the other in order to reuse some of the
elements. In XACML 3.0 we had to, because of the new features, also
import elements in the reverse direction as well. This lead to a
circular import, which seemed to cause trouble with some (many?) XML
parsers.

The options were to either duplicate the required element declarations
in two separate schemas or to merge the schemas.

I suggested we merge since it leads to less redundancy and easier
implementation since a given element, like <AttributeValue>, would have
the same namespace regardless it appears in the request/response or a
policy.

Best regards,
Erik



On 08/03/2010 05:21 PM, Farrukh Najmi wrote:
> Dear colleagues,
>
> I just started looking at XACML 3.0 draft specs and noticed that the
> policy and context schemas have been combined into a single file name
> xacml-core-v3-schema-wd-17.xsd.
>
> FWIW, in my experience it is better to keep policy (information model)
> and context (protocol) schemas in separate xsd files and namespaces.
> As such I feel XACML 2.0 had it right and XACML 3.0 combining the two
> is a step in the wrong direction.
>
> I was curious what the rationale of the TC was to make this change and
> would be grateful for some explanation. Thanks in advance.
>