Document: draft-ietf-clue-data-model-schema
Title: An XML Schema for the CLUE data model
Reviewer: Henry S. Thompson
Review Date: 2016-05-11
IETF Last Call Date: 2016-05-23

Summary: The XML Schema itself which is included in this draft is
conformant to the XML Schema 1.0 spec, and is good to go.  There is a
minor glitch in one of the XML examples, easily corrected.

Comments:

I tested the XML Schema document included as section 4 and it passes as
a valid against the schema for schemas.  The example document in section
17 is schema-valid according to the corresponding schema.  See 'Nits'
below for a minor problem with the example document in section 18.

I briefly reviewed the schema document and it seems straightforward and
fit for its intended purpose.

Minor Issues:

Section 4, lines 13--14:

 <xs:import namespace="urn:ietf:params:xml:ns:vcard-4.0"
 schemaLocation="xcard.xsd"/>

As this stands, it's not actually usable for validation purposes,
because no xcard.xsd file is supplied.  Furthermore, there is no
Appendix A, which is alleged to provide it (see 11.29.1.2).

I note further that the xCard RFC (6351) doesn't contain an XSD-format
schema document either.  The IANA XML Registry [1] schema entry for the
urn:ietf:params:xml:ns:vcard-4.0 URN namespace _does_ however link to
such a schema document [2].  I suggest you either
  a) Edit the draft so the above lines read

 <xs:import namespace="urn:ietf:params:xml:ns:vcard-4.0"
 schemaLocation="http://www.iana.org/assignments/xml-registry/schema/vcard-4.0.xsd"/>

  (this is what I did to do the validity checks I did);

or

 b) Delete the schemaLocation attribute, add a comment identifying
    possible sources of a schema document for the vcard-4.0 namespace,
    e.g. the above iana.org URI or the contents of Appendix A (if you
    fill it in).

Nits:

Section 18, the XML example has a (copy-paste?) error, which renders
that example invalid against the schema.  The line

             <encGroupIDREF>EG0</encGroupIDREF>

appears twice inside mediaCapture VC7, once on line 204 and once on line
237.  The first occurrence should be deleted.

[1] http://www.iana.org/assignments/xml-registry/xml-registry.xhtml#schema
[2] http://www.iana.org/assignments/xml-registry/schema/vcard-4.0.xsd