Re: [DNSOP] [Ext] Re: Resolver behaviour with multiple trust anchors

Edward Lewis <edward.lewis@icann.org> Tue, 31 October 2017 19:33 UTC

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From: Edward Lewis <edward.lewis@icann.org>
To: Paul Wouters <paul@nohats.ca>, Ólafur Guðmundsson <olafur@cloudflare.com>
CC: Moritz Muller <moritz.muller@sidn.nl>, "dnsop@ietf.org" <dnsop@ietf.org>
Thread-Topic: [Ext] Re: [DNSOP] Resolver behaviour with multiple trust anchors
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Date: Tue, 31 Oct 2017 19:33:16 +0000
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Subject: Re: [DNSOP] [Ext] Re: Resolver behaviour with multiple trust anchors
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On 10/31/17, 14:30, "DNSOP on behalf of Paul Wouters" <dnsop-bounces@ietf.org on behalf of paul@nohats.ca> wrote:

> On Oct 31, 2017, at 22:25, Ólafur Guðmundsson <olafur@cloudflare.com> wrote:
>>
>> There are three ways to treat this case: 
>> Any-TrustedKey-works  
>> ConfiguredKey-trumps-DS 
>> DS-trumps-configuredKey
>>
>> But I suspect the middle one is implemented 
   
>It better, it is the only working solution :)

Can you elaborate...why would it be the "only" "working" solution?

I understand that "Any-TrustedKey-Works" would be hard on implementers (I recall a day when one of the original DNSSEC developers didn't like doing something because it made the code ugly), but it's the one that maximizes robustness.

("What if:" The trust anchor manager was off-line during the time when an Automated Updates [STD 69] revocation was signaled?)

Finding the closest trusted encloser ("trusted" meaning there's a trust anchor data, as opposed to a simple "closest encloser" determined by existence) is simple, finding and handling the list of all trusted enclosure points would make the coding ugly.  That's the only rationale I'd see for not follow a philosophy of "Any-TrustedKey-Works."