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Re: Description of the 2-ways and the 4-ways handshake

From: Yves Lafon <ylafon@w3.org>
Date: Wed, 6 May 2009 16:22:37 -0400 (EDT)
To: David Singer <singer@apple.com>
cc: RaphaŽl Troncy <Raphael.Troncy@cwi.nl>, Silvia Pfeiffer <silviapfeiffer1@gmail.com>, Davy Van Deursen <davy.vandeursen@ugent.be>, Media Fragment <public-media-fragment@w3.org>, Michael Hausenblas <michael.hausenblas@deri.org>
Message-ID: <alpine.DEB.1.10.0905061619140.5004@wnl.j3.bet>
On Wed, 6 May 2009, David Singer wrote:

> At 3:55  -0400 6/05/09, Yves Lafon wrote:
>>> I think, rather
>>> ? -- it is the server's syntax and task to do the selection
>> 
>> In fact if "?" is needed, our fragment syntax is just a hint, people owning 
>> their URIs can define whatever naming scheme they want, the main issue is 
>> finding the association between identification of useful ranges someone 
>> awnts to retrieve and URIs
>
> There is a very big difference between ? and #. "?" is an instruction to the 
> server;  a database query, for example.  It is part of the definition of the 
> resource.  # is an instruction to the user-agent, a focusing instruction.

The server can interpet is in the way it wants, it is usually linked to 
cgi or db query, but it doesn't have to be the case; but my point was that 
we can't mandate the structure of what goes after a '?' in a URI, while 
with the '#', as it is targeted to the client (as you said), and we want 
the client to behave in a defined way, then we have the right to mandate a 
specific syntax.

>
>> 
>>> # -- it is the MIME type's syntax and UA's task to do the selection, 
>>> possibly assisted by an enhanced protocol with the server
>>> 
>>> That is, if the UA is asked to focus the user's attention on a certain 
>>> portion of the resource, it should do the best it can
>>> a) to do said focusing
>>> b) to use the network and server wisely
>>> 
>>> If the protocol is HTTP-1.1-enhanced, then there may be new commands or 
>>> headers it can use.  In the lack of that (e.g. HTTP 1.1 or even 1.0) it 
>>> does the best it can.
>> 
>> HTTP-1.1-enhanced ?
>> Adding a range unit is in the same class of adding a new content-type, that 
>> doesn't really qualify as "enhancing" HTTP :)
>
> Sorry, I just used the name as a short-hand. However, I think that a server 
> that can co-operate with a UA over selecting time or or sub-parts of a 
> temporal resource, is enhanced. And you need to know if the server you're 
> talking to is enhanced in this way, as well.

Yes, the implementation is enhanced, but not the protocol.

>>>>   - In the case of the '?': the normal behavior, it is a new resource 
>>>> that will be completely served with a 200 OK response code. The only 
>>>> extra specification we may add is a link header to point towards the 
>>>> original resource the segment comes from ...
>
> if it even exists.  Don't forget, the ? may be processing instructions: 
> "make me a synthetic background 20 seconds long that looks vaguely like 
> swirling water".
>
>>>> 
>>>> I suggest to write that down in the next iteration of the WD :-)
>>>>
>>>>   RaphaŽl
>>>> 
>>>> --
>>>> RaphaŽl Troncy
>>>> CWI (Centre for Mathematics and Computer Science),
>>>> Science Park 123, 1098 XG Amsterdam, The Netherlands
>>>> e-mail: raphael.troncy@cwi.nl & raphael.troncy@gmail.com
>>>> Tel: +31 (0)20 - 592 4093
>>>> Fax: +31 (0)20 - 592 4312
>>>> Web: http://www.cwi.nl/~troncy/
>>> 
>>> 
>>> --
>>> David Singer
>>> Multimedia Standards, Apple Inc.
>>> 
>> 
>> --
>> Baroula que barouleras, au tiťu toujou t'entourneras.
>>
>>         ~~Yves
>
>
> --
> David Singer
> Multimedia Standards, Apple Inc.
>

-- 
Baroula que barouleras, au tiťu toujou t'entourneras.

         ~~Yves
Received on Wednesday, 6 May 2009 20:22:51 GMT

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