W3C home > Mailing lists > Public > public-rdf-in-xhtml-tf@w3.org > February 2009

Re: CURIE objections in HTML5+RDFa

From: Manu Sporny <msporny@digitalbazaar.com>
Date: Fri, 20 Feb 2009 00:49:38 -0500
Message-ID: <499E4472.3090705@digitalbazaar.com>
To: Henri Sivonen <hsivonen@iki.fi>
CC: RDFa mailing list <public-rdf-in-xhtml-tf@w3.org>, Ian Hickson <ian@hixie.ch>
Henri Sivonen wrote:
> I'm particularly worried about ccREL succeeding to the point that an
> alternative solution can no longer be launched into the market to
> replace it and Free Culture then getting encumbered by the syntactic
> complexity preventing even further success.

Which alternative solution to ccREL are you referring to?

>> Could you provide at least one alternate mechanism? The mechanism should
>> not use full URIs, and should addresses most, if not all, of the
>> problems solved by using full URIs?
> A backwards-incompatible alternative mechanism would be tokens of the
> type "prefix-local" (or "prefix:local", but I'm trying to avoid
> confusion here) where prefix *wouldn't map to anything*. That is,
> processing would merely compare the "prefix-local" code point for code
> point without expanding it to anything. Prefixes would be from two to
> four letters--preferably acronyms for the vocabularies--

Why are we imposing arbitrary limits on prefix-names? For example, we
(Digital Bazaar and the Microformats community) have created an Audio
RDF vocabulary, and we would like people to use "audio" for the prefix
in RDFa. Granted, we can't /make/ them do that, but do make a
best-practice suggestion that they spell it out so it's easier to read
the HTML code, for those that care about such things.

The key here is that the choice is the web developers to make, not ours.

More here:


> allocated on a
> first-come-first-served basis either through a central registry 

One of the problems that full URIs address is that the solution does not
require a central registry of any kind. The centralized solution that
has been proposed above, which was mentioned several times during course
of RDFa development, does not address that concern.

More here:


> or through best-effort collision avoidance by the community.

There is no need to worry about collision avoidance when you use URIs:


> Now, how to make this backwards compatible with the RDF model? If the
> predicates don't need to be dereferencable

The W3C TAG says that they should be dereference-able, but we'll ignore
that for now since you've stated that you don't agree with the TAG. :)

> a one-letter URI scheme
> (e.g. 'r' for RDF) could be registered adding two characters of overhead
> per predicate: "r:prefix-local".
> To add back dereferencability in pre-existing software and to use a
> pre-existing registry system, a TLD called 'rdf' could be registered and
> the identifiers could take the form "http://local.prefix.rdf" with 11
> characters of overhead. If a software update for dereferencability is
> OK, "r:prefix-local" could be defined as the identifier to compare, but
> to dereference it you'd map it to "http://local.prefix.rdf" before
> passing it to the HTTP layer.

I thought your whole point was to get away from using URIs of any sort?
I'm a bit confused at this point, didn't you state that URIs were a bad
thing and we shouldn't use them at all? Or did you mean that you're fine
with URIs, just not in the HTML markup itself?

You have mentioned that you are sensitive to the costs associated with
implementing RDFa. There are additional costs with what you are
proposing as well - far above what RDFa is asking now:

There is a $50K ICANN TLD registration fee and the roughly $135K that
you will have to spend for consultants and lawyers to bring the
application all the way through the process (if it's successful). The
submitting corporation must also demonstrate that it has enough start-up
capital (more than $500K) and the expertise (people on payroll that must
draw salary) to run the registry - let's just say that at a minimum,
that is $250,000 a year. That's a $935K start-up cost plus an ongoing
$250,000/year associated with your .rdf TLD proposal, how do you think
that should be addressed?

Given this new information, how would you change the proposal you have
outlined above?

-- manu

Manu Sporny
President/CEO - Digital Bazaar, Inc.
blog: Scaling Past 100,000 Concurrent Web Service Requests
Received on Friday, 20 February 2009 05:50:20 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:50:30 UTC