[XMLVersioning-41] Noah Mendelsohn Versioning Analysis for XML Schema WG

In parallel with the Tag's analysis of versioning issues, the XML Schema 
workgroup has been looking at the problem from an XML Schema perspective. 
As part of that discussion, I prepared some notes that were posted several 
weeks ago to the members-only schema-IG mailing list.  With the permission 
of the workgroup, I am reposting them here where they can be viewed by 
non-W3C members.

This analysis does NOT represent the considered position of the schema WG, 
or for that matter of my employer (IBM).  On the contrary, other 
approaches have been suggested, and the workgroup has yet to take a formal 
position on any of the proposals.  I offer these notes in the hope that 
they will contribute to the Tags analysis of the issues and opportunities. 
 I would call your attention particularly to the two introductory sections 
titled "Assumptions and Rationale" and "Separation of Concerns", as I 
think these cover issues that should be considered for most any approach 
to versioning and evolution.

The documents were originally prepared as HTML using a relatively popular 
word processor.  I was later told that there were font problems rendering 
on Macs and some other non-Windows platforms.  Accordingly, I made a 
second copy in .txt format.  The two attachments to this note are 
identical in content except for formatting.

I hope this is helpful to the Tag in it's deliberations on versioning.

Noah



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Noah Mendelsohn 
IBM Corporation
One Rogers Street
Cambridge, MA 02142
1-617-693-4036
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