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

Edward Lewis <edward.lewis@icann.org> Wed, 01 November 2017 11:12 UTC

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From: Edward Lewis <edward.lewis@icann.org>
To: Mark Andrews <marka@isc.org>, Moritz Muller <moritz.muller@sidn.nl>
CC: "dnsop@ietf.org" <dnsop@ietf.org>
Thread-Topic: [Ext] Re: [DNSOP] Resolver behaviour with multiple trust anchors
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Date: Wed, 1 Nov 2017 11:11:57 +0000
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Subject: Re: [DNSOP] [Ext] Re: Resolver behaviour with multiple trust anchors
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On 10/31/17, 20:50, "DNSOP on behalf of Mark Andrews" <dnsop-bounces@ietf.org on behalf of marka@isc.org>; wrote:
   
>Secondly doing deepest match on trust anchors is the only secure way to prevent a parent overriding the child zone's security policy.

By this, do you mean choice of cryptographic algorithm and/or length?  To achieve "independence" in this way, the child can simply refuse to have a DS record at the parent and then lean on managing trust anchors at all relying resolvers.