W3C home > Mailing lists > Public > public-bpwg-ct@w3.org > October 2008

LC-2078: claim of conformance in a Via HTTP header

From: Francois Daoust <fd@w3.org>
Date: Fri, 03 Oct 2008 17:06:42 +0200
Message-ID: <48E63502.8040406@w3.org>
To: public-bpwg-ct <public-bpwg-ct@w3.org>

The Last Call comment
---------------------
http://www.w3.org/2006/02/lc-comments-tracker/37584/WD-ct-guidelines-20080801/2078

As text
-------
* Section 4.1.6.1 When a proxy inserts the URI to make a claim of
conformance, exactly what are they claiming -- all must-level
requirements are met? Should-level? What is the use case for this
information?


Thoughts
--------
I think that the main use case is not really for the Content Provider to 
be able to tell whether there is a CT-proxy on the line that conforms to 
the guidelines, but rather to tell that there IS a CT-proxy on the line.

That was the rationale I used to discuss it at first:
  http://lists.w3.org/Archives/Public/public-bpwg-ct/2008Apr/0040.html

and the view we had when we resolved to use the comment:
  http://www.w3.org/2008/04/29-bpwg-minutes.html#item02
  later simplified in: http://www.w3.org/2008/06/03-bpwg-minutes.html#item01

I note that the probability that a CT-proxy vendor adopts the convention 
to put "http://www.w3.org/ns/ct" as a comment in a Via header and does 
not follow the other guidelines is fairly low. Still I think this should 
be used as an ID flag ("I'm a CT-proxy"), and not as a claim ("I'm a 
CT-proxy that conforms to the spec").

I propose to resolve yes, and to update the text in 4.1.6.1 to:
[[ Proxies [...] SHOULD indicate that they have transformation 
capabilities by including a comment in the VIA HTTP header consisting of 
the URI "http://www.w3.org/ns/ct" ]]

... but then, "content transformation capabilities" is not precise 
enough, any way to make things clear?


(AFAICT, the wording changed towards "conformance" in revision 1l of the 
draft:
 
http://www.w3.org/2005/MWI/BPWG/Group/TaskForces/CT/editors-drafts/Guidelines/080712#sec-via-headers 
)

Francois.
Received on Friday, 3 October 2008 15:07:21 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Friday, 3 October 2008 15:07:21 GMT