[OGSA-AUTHZ] Your comments on Func Components

[David Chadwick]

Hi Tom

I am happy to add "used for access control" in the context of our 
document, but not secure manner or trusted source, because this is not 
true in all cases. Part of our model is to make sure that we only use 
trusted attributes because the ones that are asserted may have been done 
insecurely or may not be trusted (see our other definitions). The role 
of the CVS in our model is to make sure that only the secure and trusted 
attributes are filtered out for use, whilst the others are discarded. If 
we define attributes as secure and trusted then there cannot be other 
attributes to be discarded (by definition).  Then there is no point in 
having a CVS, its functionality is redundant.

However if you are talking from an XACML perspective then your 
definition is OK, since by the time the attributes are received by the 
XACML PDP they are already secure and trusted.

regards

David


Tom Scavo wrote:
> On 11/28/07, David Chadwick <d.w.chadwick at kent.ac.uk> wrote:
>> iii) I have added a definition of attribute "Attribute is a property of
>> an entity". Nice and simple, and all encompassing :-)
> 
> I think this defines what might be called "metadata."  Recently, we
> defined "attribute" as follows:
> 
> An attribute is information asserted in a secure manner by a trusted
> source, used for access control.
> 
> I think the key is "used for access control."  This is what
> distinguishes attributes from other kinds of data.
> 
> Tom
> 

-- 

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David W. Chadwick, BSc PhD
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