XACML Charter Scope

[Hal Lockhart <hal.lockhart@entegrity.com>]

I observed on the concall today that the proposed charter says the purpose
"is to define a core schema and corresponding namespace." I said that this
alone did not seem to me to be sufficient to allow interoperable
implementations to be developed without some statement about how documents
defined by this schema might be exchanged.

On reflection, I concede that for some applications it would probably
suffice to say that the document would be generated as a disk file and
exchanged by any method of choice. However, it is possible that the TC
wishes to go further. If XACML messages are intended to be associated with
control of access to portions of XML documents, it seems it would be useful
to describe how they would be contained in or bound to the document to which
they refer. If XACML is to be used to provision an access control system,
then a protocol for requesting and receiving messages might be useful. 

Increasing the scope in this way would in no way commit us to inventing
these mechanisms from scratch. It would be sufficient to reference a
suitable standard developed elsewhere.

Hal