RE: Question on the boundaries of content negotiation in the context of the Web of Data

Hello Xiaoshu,


Just on one small thing and then I really must do other 'stuff'...

> >> Then,> "png" and "ttl" are awww:representations of "the:house" -- 
> >> as you said - a set of ephemeral set of bits and some metadata.
> >>     
> >
> > Be careful with the prescription of this particular example 
> > in that "the:house" as in "" 
> > has never been claimed anywhere as designating a house 
> > (conceptual, actual, class or otherwise)- that priviledge was 
> > afford to "".
> >   
> Does it matter with a fragment identifier or not? I don't think so.

The HTTP protocol strips the #frag from the URI transferred in the request line. 
It is not seen by the orgin server or the caches. I understand this to be an essentail 
part of the protocol design and not a bug. So although you might ask for:

what the server see's is

It is that truncated reference that gets conneg'd, not the full reference. I believe you will find that documented on the syntax of an HTTP request in RFC 2616 (for those demanding citation).

See also (Michael that's another that you might like to add to your list if you haven't tuned out).

>  All URI should work in the same way, fragmented or not.

Well operationally, when presented in HTTP requests, they don't. 

> The difference of a 
> fragment URI and a non-fragmented one is the path to the representation 
> (either awww or pol one, it doesn't matter).  How we obtain the 
> information of something should have nothing to do with the semantics of 
> that thing.

Yes... but it is critical that we know what thing we are getting information for/about. In asking for

we (hope to) get a awww:representation of: (not of

which (we hope) has something to say about:

but apriori there are no guarantees that those hopes will be met.

> This is, in fact, the critical mistake of httpRange-14.
> > Neither, the PNG serialisation of the image or the ttl 
> > serialisation of the graph are claimed as representations of 
> > whatever is designated by "". 
> >
> I am a bit confused by the wording "Neither".  Do you mean 
> that the PNG serialization of the image can NOT be the representation of 
> ""? Or you mean it 
> can?  I opt for the "can" because I don't see any reason for me NOT to accept 
> other's claim.  And from the picture, it seems that that image is 
> intended for "".

See above... the representations in general are not *of* the thing referred to by the full URI, but of the things referenced by that URI minus #frag.

> > At best one might claim them as equivlent representations 
> > of "" but I have no idea what 
> > resource Michael intended that to be.

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Received on Friday, 13 February 2009 16:50:58 UTC