[xacml] Change Request: Issuer not required in context:Attribute

Change Request:

  In context-16f.xsd, the Issuer xml attribute of AttributeType
  is marked "required".  I request that this be changed to
  "optional".

Rationale:

  I believe we agreed that this should be optional.  It was
  optional in 15g, 15h, 15i, and 16a, then became "required" in
  16e and 16f without any group decision or discussion.

  The "issuer" is not known in the case of most attributes used
  in J2SE.  We had discussed forcing the context builder to set
  the attribute to "PEP" or "UNKNOWN" or something like that, but
  we decided it was more straightforward to make the attribute
  optional.  Accordingly, we did not allocate an identifier for
  "unknown issuer".

  [If this change request is not granted, then an identifier must
   be assigned for "unknown issuer".  I suggest
  "BASE:unknown-issuer".]

Current text in draft-xacml-schema-context-16f.xsd:

	<xs:element name="Attribute" type="xacml-context:AttributeType"/>
	<xs:complexType name="AttributeType">
		<xs:sequence>
			<xs:element ref="xacml-context:AttributeValue" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
		<xs:attribute name="AttributeId" type="xs:anyURI" use="required"/>
		<xs:attribute name="Issuer" type="xs:anyURI" use="required"/>
		<xs:attribute name="IssueInstant" type="xs:dateTime" use="optional"/>
	</xs:complexType>

Requested changed text:

	<xs:element name="Attribute" type="xacml-context:AttributeType"/>
	<xs:complexType name="AttributeType">
		<xs:sequence>
			<xs:element ref="xacml-context:AttributeValue" minOccurs="0" maxOccurs="unbounded"/>
		</xs:sequence>
		<xs:attribute name="AttributeId" type="xs:anyURI" use="required"/>
		<xs:attribute name="Issuer" type="xs:anyURI" use="optional"/>
		<xs:attribute name="IssueInstant" type="xs:dateTime" use="optional"/>
	</xs:complexType>

Anne Anderson
-- 
Anne H. Anderson             Email: 
Sun Microsystems Laboratories
1 Network Drive,UBUR02-311     Tel: 781/442-0928
Burlington, MA 01803-0902 USA  Fax: 781/442-1692