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Re: "tdb" and "duri" URI schemes...

From: Nathan <nathan@webr3.org>
Date: Wed, 03 Nov 2010 01:58:02 +0000
Message-ID: <4CD0C1AA.6020000@webr3.org>
To: Jonathan Rees <jar@creativecommons.org>
CC: Larry Masinter <masinter@adobe.com>, "www-tag@w3.org" <www-tag@w3.org>
Hi Larry,

Jonathan Rees wrote:
> On Tue, Nov 2, 2010 at 11:38 AM, Larry Masinter <masinter@adobe.com> wrote:
>> This idea has been bouncing around for such a long time,
>> but I updated the document
>>
>> http://tools.ietf.org/html/draft-masinter-dated-uri-07

I've read the drafts of this spec several times over the past year or 
two, and would suggest that there may not be any need for the tdb 
scheme, or even two distinct schemes.

Dated uri does seem like a very useful addition to the web, however it's 
semantics could be simplified as such:

    For example, "duri:2008:http://www.ietf.org" is a persistent
    identifier for "http://www.ietf.org" in 2008, and which one
    might use to describe the resource identified by
    "http://www.ietf.org" in 2008.

It appears to me that this would cover all use cases for duri and tdb, 
it's just a dated uri which you can use when you need a dated uri. The 
IETF can use it to describe themselves in 2008, internet archive can use 
it as a persistent identifier, and I can start to make statements like:

  <duri:2001:http://example> :sameas <duri:2002:http://example>;
    :differentFrom <duri:2000:http://example> .

I'm unsure whether you want to address dereferencing, perhaps better 
said as dedurieing, in the spec - but it's certainly one of the first 
things people will do with any duri, they'll chop the scheme and date 
off and do what they normally do with the uri. But perhaps this is so 
obvious that it doesn't need spec'd!

Regardless, I strongly feel that "Thing Described By" would be best 
dropped, it's confusing at the least, can you imagine how many will ask 
"what's the difference between a duri and a tdb?" and it's a valid 
question even now, "when should I use a tdb instead of a duri? and are 
the consequences of using the wrong one?" - and in reply to the reply to 
that question, if there are no consequences then why make a distinction? 
and if there are consequences then are you prepared to introduce that in 
to the web?

On a side note, is there a reason why a dated uri has a scheme, why not 
simply:

    <timestamp>:<encoded-URI>

for example:

    2006:http://www.ietf.org
    2010-11-03T01:27:12Z:http://example.org/some#message

Perhaps this wouldn't be backwards compatible thus the need for a scheme?

>   6.8.  'tdb' and levels of indirection
> 
>      The 'tdb' scheme introduces a level of semantic indirection.  The
>      puzzles and confusions about use and mention, name and reference, and
>      levels of indirection have been puzzling and amusing for quite a
>      while.
> 
> 	"It's long," said the Knight, "but it's very, very beautiful.
> 	Everybody that hears me sing it--either it brings tears into their
> 	eyes, or else--"
> 	"Or else what?" said Alice, for the Knight had made a sudden
> 	pause.
> 	"Or else it doesn't, you know.  The name of the song is called
> 	'Haddock's Eyes.'"
> 	"Oh, that's the name of the song, is it?"  Alice said, trying to
> 	feel interested.
> 	"No, you don't understand," the knight said, looking a little
> 	vexed.  "That's what the name is called.  The name really is 'The
> 	Aged Aged Man.'"
> 	"Then I ought to have said 'That's what the song is called'?"
> 	Alice corrected herself.
> 	"No, you oughtn't: that's quite another thing!  The song is called
> 	'Ways and Means': but that's only what it's called, you know!"
> 	"Well, what is the song, then?" said Alice, who was by this time
> 	completely bewildered.
> 	"I was coming to that," the Knight said.  "The song really is
> 	'A-sitting On A Gate': and the tune's my own invention."  [LOOK]
> 
> I don't see what this section contributes.

Have to disagree with Jonathan here, I actually thought this section 
helped the reader and brought clarity to the entire spec, at the least 
it seems harmless and it made me smile.

Best,

Nathan
Received on Wednesday, 3 November 2010 01:59:00 GMT

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