Re: [Driu] [Ext] How to describe various flavors of DNS resolvers

Mateusz Jończyk <mat.jonczyk@o2.pl> Tue, 15 May 2018 16:07 UTC

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Subject: Re: [Driu] [Ext] How to describe various flavors of DNS resolvers
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W dniu 15.05.2018 o 16:51, Paul Hoffman pisze:
> On May 14, 2018, at 9:46 PM, Erik Kline <ek@google.com> wrote:
>> I'm not sure I understand the benefit of trying to provide this extra
>> information.  I think clients will need to probe nameservers for their
>> capabilities.
>>
>> Do we think TLS-only nameservers are a likely operational model?
> 
> "Probe for DNS-over-TLS" is a possible outcome, but yes, there are parties who *only* want to provide privacy-enhanced resolvers. In the DOH WG, there has also been discussion of how to prevent downgrade attacks from privacy-enhanded to clear-on-port-53>
> --Paul Hoffman
IMHuO, preventing downgrade attacks will not work because there are likely going
to be environments that will block DNS-over-TLS and common DOH servers (China
comes to mind). Browsers will have to keep working for these people.

Greetings,
Mateusz