Re: [DNSOP] Draft for dynamic discovery of secure resolvers

Paul Vixie <paul@redbarn.org> Tue, 21 August 2018 19:30 UTC

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Date: Tue, 21 Aug 2018 12:30:02 -0700
From: Paul Vixie <paul@redbarn.org>
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To: Tom Pusateri <pusateri@bangj.com>
CC: David Conrad <drc@virtualized.org>, Vittorio Bertola <vittorio.bertola@open-xchange.com>, dnsop WG <dnsop@ietf.org>
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Subject: Re: [DNSOP] Draft for dynamic discovery of secure resolvers
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this, joyfully, is a very good question.

Tom Pusateri wrote:
...
> Ok, so as Vladimír said, getting back to DHCP…
>
> 1. You obviously don’t need a DoH URI option for DHCP. 2. You’re
> comfortable with DNS over UDP/53 as long as DNS Cookies are present
> and using the existing DHCP DNS options 3. You seem happy with the
> Android approach of just trying DoT with the IP address learned via
> standard DHCP DNS options
>
> Why do you care about additional DHCP options?

in my previous explaination as to the security model i follow, i noted 
that the network paths to my dhcp server and my rdns servers were 
different, and that in the dhcp case i have far more observability and 
control than in the rdns case.

it should follow therefore that i do NOT want to use UDP/53 + Cookies 
unless there is no alternative. DoT will be preferred. (DTLS or SCTP 
would be even better, but i'm only picking from items now-on-menu.)

-- 
P Vixie