042398CB-7D2B-4F4A-AFAF-5E286AB445FB@INVINET.ORG"
type="cite">Hi Ken,
I can agree with all your points, but the strange think with
your solution is that you came out with a new structure to be
maintained in UBL, and for the very first time, we are producing
structure for an extension point.
We are also creating two different signature components: a
common library UBL Signature component and another one that's used as a
wrapper inside the extension point. The use of extension points to
place the signature was originally thought as a way to incorporate
digital signatures of another namespace inside UBL documents without
breaking schema compatibility. Extensions where the only place where we
could add other stuff than UBL so it was a nice placeholder for this
kind of information. All the linkage (ID/IDREF, Xpointer) information
is suggested to enable the use of the UBL common library Signature
component.
The other question is whether the UBL Signature component has
sense or not. Personally, I think that most information in UBL
Signature component is also covered in a standard ETSI Signature
(XAdES) so you wouldn't need that component at all. Then you would only
require to place the signature in an Extension and no requirements on
Signature placeholders for UBL (that's the case BTW of the invoice,
required in some legislations in Europe but without the Signature
Component in the Invoice structure)
Another possible way of solving this would be to have a
Signature component with a "anyType" structure inside to be used as a
signature placeholder, but getting rid of all the components about
signature (such as Canonicalization Method or Signature Algorithm) and
all the reference problems.
<cac:Signature>
<cac:SignatureAttachment>
<ds:Signature>
...
</ds:Signature>
</cac:SignatureAttachment>
</cac:Signature>
I hope this helps!
Oriol
El 30/11/2009, a las 17:28, G. Ken Holman escribió:
For all those reasons, I think we need:
cac:Signature/cbc:ID ---------reference--------->
ext:UBLExtensions/ext:UBLExtension/ext:ExtensionContent/sig:Signature/cbc:ID
... with an associated:
ext:UBLExtensions/ext:UBLExtension/ext:ExtensionContent/sig:Signature/ds:Signature
But this is only my idea and I would like to
hear the opinion of others. I
feel quite confident, though, that my approach would be within the
expectations of the committee.
Nessun virus nel messaggio in arrivo.
Controllato da AVG - www.avg.com
Versione: 8.5.426 / Database dei virus: 270.14.87/2535 - Data di rilascio: 11/29/09 19:31:00