RE: How could RDDL be distributed ?

[Miles Sabin <MSabin@interx.com>]

Mark Baker wrote,
> Miles Sabin wrote:
> > The problem I want a solution to is,
> > 
> >   I have a public ID/system ID/URI for this DTD, external 
> >   entity, schema, RDDL doc, etc.; find me a server which can 
> >   give me an authoritative copy (in the case of a URI maybe a 
> >   mirror of the main server).
> >
> > or maybe rather than finding a server I just want the
> > authoritative copy itself.
>
> Or a cached copy?

Indeed ... I'd like to see distribution and replication reaching
all the way back to the client, in a similar way to HTTP caches
or DNS resolvers.

> Why bother with RESCAP when HTTP was designed to do this?  For 
> the disconnected example, set up a HTTP proxy cache on your 
> laptop, configure your browser to use it, browse to resource so 
> it may be cached, and there you go.  Other user agents on the 
> laptop can be configured to use the proxy too (e.g. JDK).

Unfortunately I don't think HTTP is a good fit here. Bear in
mind that there are serious security issues here ... malicious
subsitition of bogus DTDs/Schemas could be a serious problem.
The HTTP solution to this would be HTTPS with server side
certification. Fine, but we have a problem: in many cases won't
be able to change authoritative URIs from the http: scheme to
the https: scheme. I guess this is particularly true in the
case of documents hanging off the end of namespace URIs.

> Don't be too concerned about "hot spots".  Who knows, maybe 
> whomever maintains that document uses Akamai.  Ain't 
> abstraction wonderful?

I'm _extremely_ concerned about hot spots, and I'm not at all
convinced that Akamai type solutions will help us here.

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/