Hi Ludwig
On 26/11/2010 08:53, Ludwig Seitz wrote:
> On Thu, 2010-11-25 at 17:57 +0000, David Chadwick wrote:
>> I dont see the difference between standardising a status code in a
>> profile and standardising an Advice in a profile, except for one thing
>>
>
> There is another:
>
> To standardize an Advice Id you don't need to change the core XACML
> standard. To standardize a new status code you need to change the
> standard.
This is because the full list of codes are listed in Section B.9 (or
B.8), yes?
But what is the standard defined behaviour for a PEP that receives an
unknown status code? Is this documented anywhere? Probably not. Will
they crash? Or will they ignore it? Most likely the latter.
So if a profile defines a new status code, whilst from a pure-ist point
of view this should be in the base standard and not in a profile,
because the standard does not allow extensibility of this feature, in
practical terms it wont actually cause any problems to implementations
will it?
I can accept that Advice is the Correct thing to do for v3, but what is
the correct solution for v2?
regards
David
>
>> Advice is not available to XACMLv2 implementations
>
> Since your approach necessitates a change in core standard, backwards
> compatibility is gone either way, so I don't see a big drawback with
> using v3 specific stuff (and not changing the core v3 standard).
>
> /Ludwig
>
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