Re: [whatwg] Link rot is not dangerous

Tab Atkins Jr. schreef:
> Assume a page that uses both foaf and another vocab that subclasses
> many foaf properties.  Given working lookups for both, the rdf parser
> can determine that two entries with different properties are really
> 'the same', and hopefully act on that knowledge.
>
> If the second vocab 404s, that information is lost.  The parser will
> then treat any use of that second vocab completely separately from the
> foaf, losing valuable semantic information.
>   

If the subclass-vocabulary is public, then it is most likely already 
well taken care of by the owner and also archived in several places, and 
thus hard to get lost. If the subclass-vocabulary is one custom-built 
for a specific site, then it is likely already stored in the same location.

But even if you had RDF data without ontology, it is still far from 
useless. In fact, I’d say most RDF consumers today do not really do any 
kind of reasoning, which is what you primarily need an ontology for, 
especially not the large consumers. Without ontology you can still 
determine types, query their properties whose names are often 
self-explanatory, compare resources for equality, etc.

Knowledge of the ontology will be embedded in documentation and existing 
software that consumes the data. Let me remark that when you end up in 
this scenario, you still basically got the same as what microformats 
have to work with. And if need be, you could even manually construct a 
schema.

But yes, if everything goes awry, then data can get lost. That is the 
nature of the web. It is like, if snap.com goes out of business, all 
sites using those annoying popups will cease to show them (hurray!). A 
question you could pose is, if ‘the web’ allowed the data to get lost, 
whether that data is really important anyway.

Maybe it would ease your mind if people set up a bunch of servers which 
spider the web of data for ontology schemas, archives them and provides 
a querying mechanism? If such a thing does not exist already.

Either way, I guess kind of the basic idea is that, dereferencibility of 
RDF URIs is a convenient bonus, not a necessity, RDF can work completely 
offline. There is no requirement that ontologies must be retrieved from 
the ontology’s URIs or that there must be an ontology at all.

~Laurens

-- 
Note: New email address! Please update your address book.

~~ Ushiko-san! Kimi wa doushite, Ushiko-san nan da!! ~~
Laurens Holst, student, Utrecht University, the Netherlands
Website: www.grauw.nl. Backbase employee; www.backbase.com