On Wed, 19 Oct 2005, jeroen bekaert wrote:

> hi Jerome, all,
>
> I am afraid I do not agree. Making elements optional (or removing elements
> from the PREMIS XML Schema) because this would solve the redundancy
> between PREMIS and METS is a bad way forward. PREMIS will be used in
> conjunction with many technologies (including METS, MPEG-21 DIDL, CCSDS
> XFDU, etc.) and therefore should be defined independently of such
> technologies. For example, PREMIS - as it currently stands - can be easily
> integrated with MPEG-21 DIDL (see: a paper Herbert Van de Sompel and I
> recently submitted to the PV2005 archive:
> http://arxiv.org/ftp/cs/papers/0509/0509084.pdf).

Note that there are very few top level elements that are mandatory in
PREMIS: mainly the identifiers.

Nice to know that PREMIS can be easily integrated with MPEG-21 DIDL: we
are very interested in seeing how it can be employed in all types of
environments.

> 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.

> Let me end with a constructive note. Instead of changing the PREMIS Schema
> based on practical issues resulting from its use with METS, one may
> consider defining the PREMIS elements and attributes in a global manner
> (instead of defining them locally as is the case in the current PREMIS XML
> Schema). This would allow for the re-use of inidividual PREMIS elements
> and attributes, including XML fragments, in other technological
> environments (including METS) when needed.

Defining the elements/attributes in a global manner is a fine idea.

As for METS, doesn't this speak for some sort of profile detailing how to
use PREMIS with METS? But of course this will require some experimentation
first.

One other note-- someone recently questioned the desirability of keeping
the PREMIS schemas stable for a year. It is actually the PREMIS data
dictionary that we said we would keep stable for a year. I assume that we
will need to revise the schemas periodically as a result of experience
using them.

Rebecca
 
> best regards
> jeroen
>
>
> > I wouldn't advocate removing PREMIS elements. But making some elements
> > optional in PREMIS so that people working within a METS context can
> > decide
> > whether they want to record information within METS or within PREMIS on
> > their own is certainly an option.
> >
> > On Oct 18, 2005, at 8:35 AM, Steve Bordwell wrote:
> >
> >> Olaf,
> >>
> >> I would agree that it is essential that there is only one PREMIS
> >> metadata schema, and that multiple flavours to meet the needs of a
> >> specific application or implementation defeats its purpose as a
> >> standard.
> >>
> >> It should not be assumed that all those who use PREMIS will do so in
> >> conjunction with METS. For a number of reasons we will not
> >> initially be
> >> implementing METS. We still want to use PREMIS and are designing a
> >> database using PREMIS. From the viewpoint of a non-METS user, PREMIS
> >> therefore needs to remain a complete and coherent schema in itself.
> >>
> >> Perhaps I have missed the point, but I am concerned that if there is
> >> redundancy between PREMIS and METS, that PREMIS semantic elements will
> >> be removed in favour of elements of METS.
> >>
> >> Steve
> >>
> >> -----Original Message-----
> >> From: PREMIS Implementors Group Forum [mailto:[log in to unmask]] On
> >> Behalf Of
> >> Olaf Brandt
> >> Sent: 13 October 2005 17:53
> >> To: [log in to unmask]
> >> Subject: [PIG] mandatory elements
> >>
> >> Hi,
> >>
> >> I would like to argue, that we should provide a standard, which is
> >> clear
> >> on the one hand but which is also easily usable. Usability in the
> >> context of the real world means, that we consider that many
> >> institutions
> >> might use METS.
> >>
> >> One main result of point 5.2., metadata usage, in the PREMIS
> >> surveyreport (page 45,
> >> http://www.oclc.org/research/projects/pmwg/surveyreport.pdf )
> >> is that
> >> "METS was by far the most commonly used scheme. Survey results
> >> indicate
> >> adoption in all three types of institution, although to varying
> >> degrees:
> >> 64% of libraries, 42% of archives, and 35% of other institutions
> >> used or
> >> planned to use METS."
> >>
> >> The PREMIS group recommended the usage of METS:
> >> The following appear to be trends in practice that may ultimately
> >> emerge
> >> as best practices:
> >>
> >> ...Use the METS format for structural metadata and as a container for
> >> descriptive and administrative metadata; use Z39.87/MIX for technical
> >> metadata for still images. (Trends and conclusions, page 7)
> >>
> >> I my opinion, we should at least have a closer look, how the PREMIS
> >> Metadata schemas could be integrated in METS without too many
> >> redundancies.
> >>
> >> One of my main concerns is the split up of the PREMIS schemas in too
> >> many different flavours. That could mean a lack of common tools. If
> >> there is a way to integrate the PRMEMIS schmeas easily in METS (but
> >> being explicit enough!), I would be glad.
> >>
> >> Cheers
> >>
> >> Olaf
> >>
> >> ______________________________________________________________________
> >> __
> >> This e-mail has been scanned for all viruses by Star. The
> >> service is powered by MessageLabs. For more information on a proactive
> >> anti-virus service working around the clock, around the globe, visit:
> >> http://www.star.net.uk
> >> ______________________________________________________________________
> >> __
> >>
> >> ______________________________________________________________________
> >> __
> >> This e-mail has been scanned for all viruses by Star. The
> >> service is powered by MessageLabs. For more information on a proactive
> >> anti-virus service working around the clock, around the globe, visit:
> >> http://www.star.net.uk
> >> ______________________________________________________________________
> >> __
> >>
> >
> > Jerome McDonough, Asst. Professor
> > Graduate School of Library & Information Science
> > University of Illinois, Urbana-Champaign
> > 501 E. Daniel Street, Room 202
> > Champaign, IL 61820
> > (217) 244-5916
> > [log in to unmask]
> >
>