Re: [Doh] [Ext] Does the HTTP freshness lifetime need to match the TTL?

Martin Thomson <> Wed, 09 May 2018 00:22 UTC

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From: Martin Thomson <>
Date: Wed, 09 May 2018 00:22:12 +0000
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To: patrick mcmanus <>
Cc: Mark Nottingham <>, Paul Hoffman <>, DoH WG <>
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Subject: Re: [Doh] [Ext] Does the HTTP freshness lifetime need to match the TTL?
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On Tue, May 8, 2018 at 9:37 PM Patrick McManus <> wrote:
> Comments from you and Martin (and this text suggestion) support changing
this from normative language to advice. The other comments favor the more
deterministic behavior we currently have.

I'm just glad we're having the discussion.  There wasn't a lot of debate
about this point and now it seems like it's well-litigated.  (Beyond my
tolerance, but that's OK, I have a short attention span.)

In any case, Mark's text is an improvement; with or without the use of 2119
language.  I don't like having two sources for the same type of
information, but that is the nature of the protocol we're building.

I had hoped that we could lean more heavily on DNS, but it seems like DNS
folks want to lean more heavily on HTTP mechanisms.  That's something to
reflect on, perhaps, but not worth more debate.