Re: [DNSOP] Resolver behaviour with multiple trust anchors

Joe Abley <> Thu, 02 November 2017 16:38 UTC

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From: Joe Abley <>
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Date: Thu, 02 Nov 2017 12:38:18 -0400
Cc: Larson Matt <>, Ed Lewis <>, Moritz Muller <>, Ólafur Guðmundsson <>, Paul Wouters <>, "" <>
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To: Bob Harold <>
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Subject: Re: [DNSOP] Resolver behaviour with multiple trust anchors
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On 2 Nov 2017, at 11:04, Bob Harold <> wrote:

> I generally agree with you, but wonder if there is a performance penalty to searching every possible path before failing.  Is that a reasonable concern?

I think there's a much bigger performance penalty from returning an error to an application and requiring an end-user to do something; the small delay introduced by validating a signature chain against a different trust anchor is likely smaller than that in the event that validation subsequently succeeds and irrelevant in the case that it fails.

I think that the performance angle, whilst always worth considering e.g. for impact on scaling properties, is a red herring in this particular case. I think the focus on what policy makes sense and where it should be applied is the right one.