W3C home > Mailing lists > Public > semantic-web@w3.org > July 2006

RE: Semantic content negotiation (was Re: expectations of vocabulary)

From: Xiaoshu Wang <wangxiao@musc.edu>
Date: Tue, 25 Jul 2006 15:54:40 -0400
To: "'Reto Bachmann-Gmür'" <reto@gmuer.ch>
Cc: <public-semweb-lifesci@w3.org>, "'Semantic Web'" <semantic-web@w3.org>
Message-ID: <003801c6b024$2b030fd0$03241780@bioxiao>

-- Reto, 

> The feature is hardly implementable with traditional 
> file-based webservers, but what's the trade off? They may 
> ignore the Accept-Vocabulary header as most webservers ignore 
> the Accept and the Accept-Language header.

The HTTP protocol is not designed to do content partition.  Of course, it
cannot carry the task.  As I wrote in the latter part of that message, the
trade-off is breaking the orthogonality of protocols by asking a
transportation protocol to do query.

The difference between the Accept header and Accept-vocabulary is that the
server can ignore the former but not the latter.  If a client try to get a
JPEG image but get back a PNG instead.  The client can still figure it out
due to different MIME type retruned.  How can a client know if the returned
RDF graph is what he wanted if the server has the option to ignore the
Accept-Vocabulary? 

> If you send the following HTTP-Request to dannyayers.com:
> 
> GET / HTTP/1.1
> Host: dannyayers.com
> Accept: application/x-turtle
> Accept-Language: en
> 
> You'll get a lot of triples your client probably can't deal 
> with, if Danny turns on inference on the server you would get 
> many triples the client could infer itself, as more RDF is 
> transferred over HTTP plain serialization negotiation will no 
> longer be enough.

I am not sure if I understand you.  What you suggested seems more expensive.
If the eventral RDF set were made from vocabularies of n different
namespace.  The inference will be conducted at n places, instead of once (at
client side).  Inference is not exactly a cheap process.  I am not sure
where you are going at?

Xiaoshu
Received on Tuesday, 25 July 2006 20:12:56 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 21:45:11 GMT