2)      Adding a generalized extensibility capability to the UR definition would be very nice, since it would permit non-resource information to be described much more easily.  It is recommended that this be done through updates to the definition of the UsageRecord and JobUsageRecord elements such that each allows an arbitrary number of extra elements not in the UR namespace after the main content of the record. It is not recommended that this be done through updating the UsageRecordType type because that leads to problems with some XML deserializers (apparently; I'm no expert on this aspect). Thus, for example, the JobUsageRecord schema definition would become:

<xsd:element name="JobUsageRecord" substitutionGroup="urwg:Usage">

        <xsd:complexType>

                <xsd:complexContent>

                        <xsd:extension base="urwg:UsageRecordType">

<xsd:sequence>

<xsd:any namespace="##other"

minOccurs="0"

maxOccurs="unbounded"

processContents="lax"/>

</xsd:sequence>

<xsd:anyAttribute namespace="##other" processContents="lax"/>

</xsd:extension>

                </xsd:complexContent>

</xsd:complexType>

</xsd:element>

        Evaluation: Extensibility issues. Extensibility is OK for resources, but may not be sufficient for non-resource attributes (e.g. job descriptor). Discussion is deferred until specific comments are dealt with.

14b)    Additionally, the role (such as VO admin, student ...) of a user might influence issues like charging or quota enforcement. It would therefore be good to have an additional element "UserRole" (might also be a part of the element UserVO that we proposed above).

Evaluation: Extension