Re: [quicwg/base-drafts] Field Terminology in QPACK Security Considerations (#4009)

Mike Bishop <notifications@github.com> Wed, 19 August 2020 13:26 UTC

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Date: Wed, 19 Aug 2020 06:26:53 -0700
From: Mike Bishop <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] Field Terminology in QPACK Security Considerations (#4009)
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@MikeBishop commented on this pull request.



>  
 To improve compression performance of this option, certain entries might be
 tagged as being public. For example, a web browser might make the values of the
 Accept-Encoding header field available in all requests.
 
-An encoder without good knowledge of the provenance of header fields might
-instead introduce a penalty for a header field with many different values, such
-that a large number of attempts to guess a header field value results in the
-header field not being compared to the dynamic table entries in future messages,
-effectively preventing further guesses.
+An encoder without good knowledge of the provenance of field values might
+instead introduce a penalty for a field name with many different values, such

Shorthand, I think.  What it's trying to express is that if there are many field lines in the dynamic table which have the same field name and distinct values, you might with some probability ignore the dynamic table when encoding.  The more entries, the higher the probability you should ignore them all to frustrate an attacker.

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