>> I also doubt that the aforementioned redundancy problem is intrinsic to
>> the combination of METS and PREMIS only. I notice a similar overlap
>> between the METS CHECKSUM & CHECKSUMTYPES attributes and elements from
>> the
>> W3C XML Signature Standard; dito with regard to the METS BETYPE &
>> EXTTYPE
>> attributes and elements from the ISO MPEG-7 MDS Standard. Are there any
>> plans to change those International Standards as well?
>
> The PREMIS Working Group spent a lot of time on digital signatures and
> brought in a few experts outside the group. We agreed that it needed to be
> compatible with XML signatures and many of the elements are the
> same. However, we did add a few elements that we felt were needed in the
> PREMIS context that weren't in XML signatures. I wouldn't think there
> would be a need to change XML signatures-- I can't speak to the others.
>

I am very happy you acknowledge the importance of being compatible with
W3C XML Signature. That's why, I think, the PREMIS XML Schema should adopt
and import the W3C XML Signature Schema as the basis for expressing digest
and signature information. If desired, additional signature related
information - that cannot be expressed using the W3C XML Signature Schema
- can still be provided under the PREMIS Namespace.

The (re-)use of International (e.g. ISO, IEC, etc.) and Web (e.g. W3C,
IETF, etc.) Standards - imo - is of utmost importance in the context of
digital preservation. If only because of their wide adoption, possible
industry backing, stability (due to the standardization process),
availability of documentation, existence of reference software, guarantees
regarding future emergence of compliant migration tools, and so on.

jeroen