Re: I-D Action: draft-nottingham-safe-hint-06.txt

Brian E Carpenter <> Fri, 13 February 2015 01:23 UTC

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Date: Fri, 13 Feb 2015 14:23:12 +1300
From: Brian E Carpenter <>
Organization: University of Auckland
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Subject: Re: I-D Action: draft-nottingham-safe-hint-06.txt
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So, I am seriously wondering how the IETF would react to a
proposal to standardise some other kind of hint in HTTP requests.
For example, if you happen to like or hate the colour green,
and/or ecologically-friendly solutions, how about a standard which
contains text like the following?

4. Security Considerations

   The "green" preference is not a secure mechanism; it can be inserted
   or removed by intermediaries with access to the request stream (e.g.
   for "http://" URLs).  Its presence reveals limited information about
   the user, which may be of small assistance in "fingerprinting" the

   By its nature, including "green" in requests does not assure that all
   content will actually be green; it is only when servers elect to honor
   it that content might be "green".

   Even then, a malicious server might adapt content so that it is even
   less "green" (by some definition of the word).  As such, this
   mechanism on its own is not enough to assure that only "green" content
   is seen; those who wish to ensure that will need to combine its use
   with other techniques (e.g., content filtering).

   Furthermore, the server and user may have differing ideas regarding
   the semantics of "green."  As such, the "greenness" of the user's
   experience when browsing from site to site might (and probably will)

The more I look at this draft, the less it seems like a meaningful idea.
The latest tweaks don't help.