Re: Re: Feedback on content transformation guidelines ( LC-2066 LC-2067 LC-2068 LC-2069 LC-2070 LC-2071 LC-2073 LC-2072 LC-2074 LC-2075 LC-2076 LC-2077 LC-2078 LC-2079 LC-2080 LC-2081 LC-2082 LC-2083 LC-2084) ( LC-2324)

 Dear Luca Passani ,

The Mobile Web Best Practices Working Group has reviewed the comments you
sent [1] on the Last Call Working Draft [2] of the Guidelines for Web
Content Transformation Proxies 1.0 published on 6 Oct 2009. Thank you for
having taken the time to review the document and to send us comments!

The Working Group's response to your comment is included below, and has
been implemented in the new version of the document available at:
http://www.w3.org/TR/2010/WD-ct-guidelines-20100211/.

Please review it carefully and let us know by email at
public-bpwg-comments@w3.org if you agree with it or not before 11 March
2010. In case of disagreement, you are requested to provide a specific
solution for or a path to a consensus with the Working Group. If such a
consensus cannot be achieved, you will be given the opportunity to raise a
formal objection which will then be reviewed by the Director during the
transition of this document to the next stage in the W3C Recommendation
Track.

Thanks,

For the Mobile Web Best Practices Working Group,
Dominique Hazaël-Massieux
François Daoust
W3C Staff Contacts

 1. http://www.w3.org/mid/4B0BEF52.5040302@eunet.no
 2. http://www.w3.org/TR/2009/WD-ct-guidelines-20091006/


=====

Your comment on 4.1.5.1 Content Tasting:
> Francois Daoust wrote:
> > For clarification, the guidelines do not build on the assumption that
> 
> > GET is not safe.
> >
> > The mechanism described by Luca is actually recommended by the 
> > guidelines: send a GET with original headers, then send a request
> with 
> > modified headers if the first response is a "request unacceptable" 
> > response.
> 
> Francois, this is not what I meant. What I meant is "content tasting".
> 
> Proxies should send a GET with original headers and if they get a 
> response (which they probably will), they should smell the response and
> 
> figure out whether that content may be good enough for mobile (and err
> 
> on the side of assuming it is). If the content is likely to be OK for a
> 
> mobile device, no transcoding should take place at all.
> 
> This is explicitly ruled out by 4.1.5.1:
> 
> http://www.w3.org/TR/ct-guidelines/#sec-content-tasting
> 
> 
> "The theoretical idempotency of GET requests is not always respected by
> 
> servers. In order, as far as possible, to avoid misoperation of such 
> content, proxies *should* avoid issuing duplicate requests and 
> specifically *should not* issue duplicate requests for comparison
> purposes."
> 
> 
> There was no reason to add this part, except, as I mentioned in my
> first 
> message, to help novarra, whose transcoder does not behave this way.
> 
> Luca


Working Group Resolution (LC-2324):
We agree and have removed the inconsistency in 4.1.5.1. Content tasting
whereby the unaltered request is sent first is encouraged by the
guidelines.

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Received on Thursday, 11 February 2010 22:32:05 UTC