[websec] Is sniffing a heuristic? (was Re: more on sniffing)

Adam Barth <ietf@adambarth.com> Sun, 08 January 2012 21:03 UTC

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From: Adam Barth <ietf@adambarth.com>
Date: Sun, 08 Jan 2012 13:03:26 -0800
Message-ID: <CAJE5ia8dVwtr5Qe3DqyrDiFk7B0_3nEJD50=RewXK5RbB37LMQ@mail.gmail.com>
To: Larry Masinter <masinter@adobe.com>
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Cc: "IETF WebSec WG (websec@ietf.org)" <websec@ietf.org>
Subject: [websec] Is sniffing a heuristic? (was Re: more on sniffing)
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On Sun, Jan 8, 2012 at 12:55 PM, Adam Barth <ietf@adambarth.com> wrote:
> On Sun, Jan 8, 2012 at 9:12 AM, Larry Masinter <masinter@adobe.com> wrote:
>>      <t>Sniffing is by its nature a heuristic process, because there are
>>      many situations where content matches the signatures and capabilities
>>      of many different possible content-type values.
>
> I disagree with this statement as well.  The sniffing we're talking
> about here is not a heuristic.  It's a historical anomaly that needs
> to be corrected for in order for user agents to be compatible with
> some web sites.

Let me expand this point some more.  Does you view the HTML5 parsing
algorithm a heuristic?  The sniffing algorithm is the same sort of
thing as the HTML5 parsing algorithm in that it's a somewhat
unpleasant algorithm for interpreting responses from servers that's
compatible with existing deployments.

Adam