[gcs-pcs-list] on using URIs

[Alf Eaton]

On 01 Mar 2006, at 10:44, Mike Rylander wrote:

> On 3/1/06, Robert Sanderson <azaroth at liverpool.ac.uk> wrote:
>>
>> On Tue, 28 Feb 2006, Daniel Chudnov wrote:
>>> The case for URIs includes:
>>
>>> - they refer to the same thing across applications
>>
>> Which is great, but not interesting for unapi surely where the use  
>> case
>> is 'I want this that I see now' not 'I want the thing identified  
>> by X'
>>
>>> - they imply some measure of identifier persistence
>>
>> Which is a disadvantage because it means that dynamic content  
>> which is
>> not persistent is less appropriate for unapi.  If the use case is 'I
>> want what I see now' (copy), not 'I want to refer back to this in the
>> future' (citation), then this means that we're adding hindrances.
>
> Well, they don't have to though.  If Alf's blog posts use day granular
> tag URIs, then the persistence is valid for that one day.  If my
> catalog uses year granular tags then I should do my best to make sure
> that the records are available for the entire year (or use a more
> granular time specifier).  To put it another way, the time specifier
> defines the "horizontal (temporal) persistence", the sub-URI at the
> end defines the "vertical (cross-app) persistence", and as an added
> bonus, the "authority identifier" can tell us where to go looking for
> an unapi server.

I don't interpret the date part of tag URIs as working that way. The  
date should identify when the tag was coined (so as to distinguish it  
from someone else using the same authority at a later date), but  
should resolve to the same item for perpetuity.

eg  <tag:hublog.hubmed.org,2006://2.1319> should always refer to the  
same post, regardless of where it's stored,

whereas if someone else buys my domain and uses the tag

<tag:hublog.hubmed.org,2010://2.1319>

that will identify their post, forever, instead.

alf.