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

Tony Finch <dot@dotat.at> Mon, 14 May 2018 11:15 UTC

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Date: Mon, 14 May 2018 12:15:36 +0100
From: Tony Finch <dot@dotat.at>
To: Paul Hoffman <paul.hoffman@icann.org>
cc: Miek Gieben <miek@miek.nl>, DoH WG <doh@ietf.org>
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Subject: Re: [Doh] [Ext] Does the HTTP freshness lifetime need to match the TTL?
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Paul Hoffman <paul.hoffman@icann.org> wrote:
>
> To me, "may use the time remaining before expiration" does not sound a
> requirement, or even an expectation.

RFC 4035, section 5.3.3

   If the resolver accepts the RRset as authentic, the validator MUST
   set the TTL of the RRSIG RR and each RR in the authenticated RRset to
   a value no greater than the minimum of:

   o  the RRset's TTL as received in the response;

   o  the RRSIG RR's TTL as received in the response;

   o  the value in the RRSIG RR's Original TTL field; and

   o  the difference of the RRSIG RR's Signature Expiration time and the
      current time.

Tony.
-- 
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