[wg11] Re: [step-os] Using STEPMod XML Representation of EXPRESS

[David Price]

Ed and company,

To clarify, STEPMod is the modules publication infrastructure. As such, the
STEPMod DTD was based only on requirements for producing a documented schema
using XSLT. Requirements for any other use of EXPRESS (e.g. validating data
against EXPRESS rules or mapping to MathML) were not considered. I was
unaware of the Japanese ballot comment on Part 28 E2 and so can't comment on
their requirements. Adapting Part 28 E1 may be exactly what they want, or
they may need something else entirely.

The STEPMod DTD was not put through the ISO process because of the overhead
and delay involved and because it wasn't intended for use in Industrial Data
application scenarios - it just had to work for STEPMod, not be perfect. It
also seemed unnecessary to use ISO ballots to deal with the modules
publication infrastructure as any delay could mean a delay in getting an
AP/module approved. Personally, I doubt if the STEPMod developers are
convinced any benefits outweigh that risk, even today. One very practical
point is that I imagine putting the DTD through an SC4 ballot would result
in people wanting to "fix" bits they don't like and I am sure nobody who
funded STEPMod wants to fund changes to it based on the whims of a ballot
resolution workshop.

For the purpose of my particular open-source project, I've found the STEPMod
DTD sufficient. I was asking if others have had a similar experience. My use
of the term "de facto standard" seems to have raised concerns. Perhaps
"open-source implementers agreement" would have been more appropriate as I
intended on experimenting with adapting some UML concepts to EXPRESS and
sharing the code. 

Regardless of anything else that might happen, I think Josh volunteering to
work on a user guide to be made freely available on the Web is great.

Cheers,
David

> -----Original Message-----
> From: wg11-bounces at steptools.com [mailto:wg11-bounces at steptools.com] On
> Behalf Of Ed Barkmeyer
> Sent: 07 September 2004 21:06
> To: Joshua Lubell
> Cc: SC4 WG11; STEP Open-Source
> Subject: [wg11] Re: [step-os] Using STEPMod XML Representation of EXPRESS
> 
> Joshua Lubell wrote:
> 
> > But Ed, if the STEPmod spec were to be included in Part 28, then it
> > would become the property of ISO. People would have to buy Part 28 from
> > ISO in order to read the STEPmod spec.
> 
> How many people in the world should ever have to read the STEPmod spec
> for XML rendition of an EXPRESS schema?  About 7, I would guess, all of
> whom are no doubt NB experts participating in SC4.  (And they can get
> SC4 documents free from ISO.)
> 
> > I would much rather see the
> > STEPmod spec published independent of ISO so that it can be freely
> > distrubuted. Otherwise, we're not likely to see much STEPmod-based
> > implementation outside of those already active in SC4.
> 
> I'm not sure what this means, but I would hope that exchanging ISO
> copyrighted EXPRESS schemas in any form is a rare occurrence in STEP
> implementation.
> 
> > I think the way to go is to first publish the spec as a freely available
> > technical report. It can then be adapted for Part 28 if SC4 so wishes.
> > But ISO should not be the first venue in which it is published.
> 
> By this logic, we should certainly stop making standards in WG11,
> because people would have to buy them from ISO, instead of inventing
> their own and publishing technical reports online.  That certainly
> applies to Part 14, 25, and 27, which didn't need to be ISO standards,
> and to Part 28, on which there has never been consensus.  And this logic
> should apply to Part 25v2 and binary exchange of STEP data.  Indeed, any
> future 20-series spec should be a technical report in the open software
> community and not an ISO standard, so as to maximize its accessibility.
>   Right?
> 
> That the ISO publication control process interferes with adoption of ISO
> standards has been an issue in several ISO communities in the recent
> past.  But we can't solve that problem -- it is out of our scope.  Our
> scope is to support the SC4 standards community as constituted, warts
> and all.
> 
> My concern is that Part 28, an ISO project SC4 intended to serve this
> same community, is required to specify a mechanism for representing
> EXPRESS schemas in XML.  If David and Josh think the most useful
> representation is the STEPmod representation and others agree, then
> surely that should be the proposed standard.  In any case, STEPmod
> should not refuse to allow its representation to be the Standard
> representation and simultaneously suggest that it be the "de facto
> standard" in the STEP community, IN LIEU OF the ISO standard
> representation.  What does Josh suggest Part 28 should standardize?
> (It's a little late to vote No on the NWI.)
> 
> -Ed
> 
> P.S.  The NIST goal in this whole effort was to get SC4 to agree to
> *common* XML representations.  Et tu, Brute?
> 
> --
> Edward J. Barkmeyer                        Email: edbark at nist.gov
> National Institute of Standards & Technology
> Manufacturing Systems Integration Division
> 100 Bureau Drive, Stop 8264                Tel: +1 301-975-3528
> Gaithersburg, MD 20899-8264                FAX: +1 301-975-4694
> 
> "The opinions expressed above do not reflect consensus of NIST,
>   and have not been reviewed by any Government authority."
> _______________________________________________
> wg11 mailing list
> wg11 at steptools.com
> http://lists.steptools.com/mailman/listinfo/wg11