RE: How could RDDL be distributed ?

[Miles Sabin <MSabin@interx.com>]

Eric van der Vlist wrote,
> We can probably learn from recent experiences to give a hint on
> how this could be achieved and I'd suggest that we give the 
> possibility to define alternative locations at the 3 places 
> where it seems possible to do so (by order of precedence):
>
> 1) Like it's specified by W3C XML Schema, and like it's the 
> case with XSLT, the APIs should allow to define alternative 
> locations for the RDDL documents.
<snip/>
> 2) Still like it's the case for W3C XML Schema or XSLT, it 
> should be possible to define alternative locations in the 
> instance documents.
<snip/>
> 3) It should be possible to define alternate locations in the 
> RDDL documents themselves. 
<snip/>
> These mirrors locations and the hints to let applications know 
> how/when they should use the mirrors might be defined as RDDL 
> resources... 

I completely agree the (SAX) entity resolver approach isn't the
way to go (too opaque, too hardwired into code). But I really 
don't like the idea of manually splattering XML document 
instances with alternative locations either ... simply too hard 
to maintain. Not to mention there's a rather serious backwards 
compatibility issue: we can't make this work for anything which 
doesn't already accomodate alternative URIs, in particular 
external DTDs.

> The next thing if we'd want to go in this direction would 
> probably be to facilitate the management of the replication of 
> RDDL documents.
>
> Things such as a version id and a time to live borrowed from 
> DNS systems could be of use.

I think that _this_ is really where we need to start. 

> These are just first thoughts about this issue that --unless I 
> have missed some exchanges-- doesn't seem to have surfaced yet.

I raised something along these lines here,

  http://lists.xml.org/archives/xml-dev/200101/msg00068.html

And Michael Mealling followed on in a different thread with some
comments on the IETF rescap stuff.

Cheers,


Miles

-- 
Miles Sabin                               InterX
Internet Systems Architect                5/6 Glenthorne Mews
+44 (0)20 8817 4030                       London, W6 0LJ, England
msabin@interx.com                         http://www.interx.com/