SSTC wants us to discuss "ValueType"

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

Note: the proposed SAML "ValueType" correspond[ed] to our
DataType.

-------------forwarded from SSTC---------------
> 5. ValueType
> 
>    Comment: Reconsider making this "required" instead of
>      "optional".  Other standards groups have discovered that a
>      data type is necessary in the Attribute metadata in order to
>      handle type checking.  Having it be optional means only
>      certain Attributes can be handled easily by systems that
>      require type checking.

On reflection, we would actually like to eliminate ValueType.  The 
theory is that, given the unconnectedness/skew of this notion to the 
xsi:type method of governing attribute values, plus the lack of 
expressed need by native SAML users for a URI-based typing mechanism, 
this is best done by the addition of a global attribute through 
<anyAttribute>; this puts the burden of semantic clarity on the definer.

So we are anticipating that the XACML profile of SAML may define one or 
more attributes here, most urgently something like an xacml:ValueType 
attribute; you would be free to prohibit any further extension.  Our new 
Baseline Attributes document would explain how to do this. (Note that 
you would be free to define such XACML extensions using XML Schema if 
you wished, though the <anyAttribute> formulation doesn't require it.)

We specifically were hoping for feedback on the acceptability of adding 
an XACML-specific ValueType attribute vs. having a SAML-native ValueType 
attribute.
-------------------end of forward--------------------------
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