Some good stuff in this presentation the IF could might want to think about...
> > From: Art Botterell <acb@incident.com>
> > Date: Sun May 11, 2003 9:07:33 PM US/Eastern
> > To: allenwyke@nc.rr.com
> > Subject: Fwd: [asn1xml] XML Europe 2003
> >
> > I imagine you've seen this?
> >
> >> Date: Thu, 08 May 2003 13:14:08 +0100
> >> From: John Larmouth <j.larmouth@salford.ac.uk>
> >> To: asn1dev@oss.com, asn1xml <asn1xml@oss.com>
> >> Subject: [asn1xml] XML Europe 2003
> >>
> >> I attach the slides I used for this presentation (you will have seen
> >> some before!).
> >>
> >> It went down pretty well, but the audience was only about forty
> >> people (five parallel sessions). But I got quite a few nods on some
> >> of my points, such as discussion of the importance of canonical
> >> encodings, and the statement that if we had patented TLV in 1980 XML
> >> would not exist today! (Or at least, would have been in violation of
> >> the TLV patent on nested self-identifying and self-delimiting
> >> elements in an encoding.)
> >>
> >> Two or three people came up aftwerwards and said how much they had
> >> learned, which was pleasing.
> >>
> >> A number of questions, most were positive or for clarification, with
> >> only a few slightly awkward questions:
> >>
> >> 1) How could ASN.1 claim to be a general-purpose data-modelling
> >> language when it did not allow the general net represented by ID and
> >> IDREF? (I said the concern was with document content, not semantic
> >> relationships between parts of that content, but that the issue of
> >> ASN.1 support in this area was still under discussion.)
> >>
> >> 2) Had any tool vendors provided a SAX or DOM-like interface to an
> >> ASN.1 (XER) decoder? (I ummed and arrghed about commercial
> >> confidentiallty, but no tool known to be publicly available, but I
> >> was rescued by another member of the audience who said "No-one in
> >> their right mind would want a DOM or SAX interface if there was code
> >> to marshall into a C, C++, or Java datastructure".)
> >>
> >> 3) Did I know about the XSD mapping into Java? (I had to admit I
> >> did not, but I said that ASN.1 implementors tended to prefer the C
> >> mapping, as the application ran faster.)
> >>
> >> There were two other presentations that are worth commenting on, both
> >> given by Henry Thompson, who seems to be very much part of XSD
> >> standardisation.
> >>
> >> The first was describing "bugs" that were going to be mended in XSD.
> >> There were three areas that he covered that seem relevant to ASN.1
> >> work:
> >>
> >> a) XSD is not properly aligned with 8601 for time types, and this
> >> needs to be addressed.
> >>
> >> b) XSD does not conform to the RFC for Base64, and this needs to be
> >> mended.
> >>
> >> c) There is a user-demand for relational constraints between parts
> >> of the document (if this integer field has value 29 that that
> >> optional element has to be present), and this has to be addressed by
> >> future work.
> >>
> >> d) There is a demand for being able to specify precision in decimal
> >> floating-point.
> >>
> >> There were other points, but these were the main ones. It makes me
> >> worry about how much work we may have to do in the future in both
> >> X.693 and X.694 to track XSD.
> >>
> >> The second presentation was also by Henry. (He also attended my
> >> presentation, and we had a good chat afterwards, and I think we both
> >> appreciated each other.) This one was about determinism, and seemed
> >> also highly relevant to our ASN.1 work (our Annex B). He has almost
> >> completed a theoretical mapping (which is being transformed into a
> >> tool) from XSD into a finite state automata, with the names of XML
> >> elements as the labels on the state transition arrows. (What he
> >> calls "exponents" - repetitions that have both a maxoccurs and a
> >> minoccurs - give him the most trouble). Having done the mapping,
> >> then a lot of old academic stuff can be applied to determine if the
> >> defined finite state machine is deterministic or not. Hence you can
> >> determine whether the XSD is valid or not (in terms of determinism).
> >> I am not sure whether this is just seen as an academic exercise, or
> >> whether it may eventually impact the XSD specification. Clearly the
> >> same approach could be done to determining formally and precisely
> >> whether an EXTENDED-XER spec violates determinism or not, but it
> >> would require work.
> >>
> >> All in all, some interesting sessions, and probably useful publicity
> >> for ASN.1, but conferences like this are really just too big to get
> >> to know people if you don't know them already (I said hello to a few
> >> OASIS people, including Karl and Jon and Mark, and had a chat with
> >> Patrick the CEO, but there is nothing really to report on that).
> >>
> >> John L
> >>
> >> --
> >> PLEASE NOTE - As an anti-SPAM measure, e-mails will shortly
> >> not be accepted by my machine from an unknown sender unless
> >> the subject contains the phrase "Hi John".
> >>
> >> If you pass my e-mail address to others (which I am very happy
> >> for you to do) please tell them to include this phrase in the
> >> subject line of their first mailing to me. Thanks.
> >>
> >> Prof John Larmouth
> >> Larmouth T&PDS Ltd
> >> (Training and Protocol Development Services Ltd)
> >> 1 Blueberry Road
> >> Bowdon j.larmouth@salford.ac.uk
> >> Cheshire WA14 3LS (put "Hi John" in subject)
> >> England
> >> Tel: +44 161 928 1605 Fax: +44 161 928 8069
> >>
> ----
>
> >
> -------------------
> R. Allen Wyke
> allenwyke@nc.rr.com
> Fax: 508.526.0729
--
R. Allen Wyke
Chair, Emergency Management TC
emtc@nc.rr.com
http://www.oasis-open.org/committees/emergency