Qualifications and Namespaces

I would not be surprised if I don't adequatley understand the topic covered
by section 3 of the primer: "Advanced Concepts I: Namespaces, Schemas &
Qualification 
Section" This leads to the concern expressed in the latest XML Signature
spec:

        2. We are not confident that our use of schema namespaces 
        and qualifications provides a single schema that can be used for 
        enveloped signatures (signature within content being signed), 
        enveloping signatures (content is within signature being signed) and 
        detached signatures (over data external to the signature document). 
        [1] http://www.w3.org/TR/2000/WD-xmldsig-core-20000510/

Specifically, I'm not sure why setting attributeFormDefault="unqualified"
(but not the elements) seemingly solved my problem with the examples I was
playing with [3]. Basically, I hope our schema instance [2] would permit
people to create Signature instances that look like:

Enveloped using ns default:
<foreign xmlns="...">
  ...
  <Signature xmlns="..."> ... </Signature>
</foreign>

Enveloped using explict prefixes:
<fo:foreign fo:xmlns="...">
  ...
  <ds:Signature ds:xmlns="..."> ... </ds:Signature>
</fo:foreign>

Enveloping using default:
<Signature xmlns="...">
  ...
  <Object>
     <foreign xmlns="..."> ... </foreign>
  </Object>
</Signature>

Enveloping using explicit prefixes:
<ds:Signature ds:xmlns="...">
  ...
  <ds:Object>
     <fo:foreign xmlns="..."> ... </fo:foreign>
  </ds:Object>
</ds:Signature>

And I hope we don't deploy something that works with our present examples
but doesn't permit someone else, later, to do some reasonable sort of thing.
Given our present schema, how well founded is this hope? <smile/>

[2]
http://www.w3.org/TR/2000/WD-xmldsig-core-20000510/xmldsig-core-schema.xsd
[3] http://www.w3.org/TR/2000/WD-xmldsig-core-20000510/#sec-Schema

_________________________________________________________
Joseph Reagle Jr.   
W3C Policy Analyst                mailto:reagle@w3.org
IETF/W3C XML-Signature Co-Chair   http://www.w3.org/People/Reagle/

Received on Friday, 12 May 2000 16:34:40 UTC