rs parameter in encrypted content coding

Martin Thomson <> Thu, 08 December 2016 18:33 UTC

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From: Martin Thomson <>
Date: Fri, 09 Dec 2016 03:29:39 +0900
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To: HTTP Working Group <>, "Manger, James H" <>
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Subject: rs parameter in encrypted content coding
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James opened this:

I'm close to pushing a new version based on what we discussed at the
meeting.  This would seem to be an open issue.  Here are the choices:

1. what we have now, rs = record without authentication tag
2. what James suggests rs includes auth tag
3. something else

My original hope was to avoid having any potential values that were
invalid, but we already got there with padding (rs=0,1,2 are all

Personally, I don't find the lack of generality to be problematic, but
I agree that the choice is a little arbitrary.  I'd be interested in
hearing what other people think.