Subject: XML DTD information

From: Kirrily Robert <[email-masked]>
Date: Tue, 05 Dec 2000 11:15:10 -0500

Greetings,

I've recently joined this list, and have been going through the
archives.

I see a lot of traffic on the topic of an XML DTD and/or schema to
describe iCalendar data.  Is there a site where I can find further
information on this?

Thanks in advance,

K.

-- 
Kirrily "Skud" Robert
[email-masked] (work)
[email-masked] (home)

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From: John Stracke <[email-masked]>
Date: Tue, 05 Dec 2000 11:45:01 -0500

> describe iCalendar data.  Is there a site where I can find further

No, it didn't really go anywhere.  The Internet-Draft seems to have
expired by now.

--
/=================================================================\
|John Stracke    | http://www.ecal.com |My opinions are my own.   |
|Chief Scientist |================================================|
|eCal Corp.      |But how do we know destroying the Van Allen belt|
[email-masked]|will kill all life on Earth if we don't try it? |
\=================================================================/

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From: "Greg FitzPatrick" <[email-masked]>
Date: Wed, 6 Dec 2000 15:04:12 +0100

Yes the XML question was sometimes quite heatedly discussed.

Here is Frank's draft - out of date but not forgotten.

http://www.globecom.net/ietf/draft/draft-dawson-ical-xml-dtd-01.html

The XML issue had a lot to do with loss of interoperability as well as the
diverging product strategies of the parent companies of several of the
CALSCH WG participants.

When the XML question was raised, I believe first by Surendra Reddy from
Oracle,  iCal had already reached a relatively high level of
interoperability, counting several major application providers amongst its
implementers. There were fears that embracing XML would lead to
dis-interoperability.  It will be obvious to any software engineer, when
given a choice, that an infostructure technology that allows nesting,
name-spaces and schemas is a better vehicle for their creative ideas than a
flat infostructure technology that doesn't do much more than get along well
with the current mail protocol standards.

Don't get me wrong though, when this came up, iCal and vCard objects were
alive and well on millions of peoples computers,  XML was a great idea with
almost no existing applications and entrenched in a lot of controversy to
boot.

If I remember correctly from Oslo - one side wanted a totally one2one
mapping of 2445 into a DTD and the other side wanted to get started right
away with "improving" things.

Furthermore CAP was already taking up a lot of delegates energy and the
thinking was; let us just get CAP under our belts and then we can turn our
attention to XML (and SKiCal for that matter)

As a sideline I can say that we have developed SKiCal in both mime-directory
and dtd/schema forms from the beginning of our work almost three years ago.
(We actually began with Dublin Core metatags.)

Last Christmas I wrote a mail to some of the members of this list and some
W3C people.  I proposed a joint IETF/W3C working group (á digital
signatures) to develop  an XML iCal schema.  Though I received support from
W3C folks (Tim Berners-Lee and Dan Connolly among others) there was less
enthusiasm from the IETF side.  After a short flurry of email - the last I
heard of this was in a conversation with Scott Bradner here in Stockholm.
"We are talking about it", he said.  But then things just died down.

If you are interested, there is a RDF model of iCal/SKiCal in the W3C
archives (written by Jonas Liljegren) as well as a review of iCal which Tim
BL wrote (I don't think he read 2445 very carefully) considering iCal/SKiCal
as a candidate for RDF-isation.

I am CC:ing this to  Surendra and Lisa who where part of the original XML
thrust and no longer populate this list to see if they want to set the
record straight for historical purposes my version is of course is sheer
MHO.

Lastly, here is a pointer to a short tutorial comparing "flat" and "nested"
object publishing.

http://www.metamatrix.se/presentationer/html/tutorial/chap1.htm

If you will be in San Diego, I will gladly elaborate.

Greg

Greetings,

Thanks in advance,

K.