Re: [Doh] panel discussion on DoH/DoC

Eliot Lear <lear@cisco.com> Mon, 11 February 2019 12:11 UTC

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From: Eliot Lear <lear@cisco.com>
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Date: Mon, 11 Feb 2019 13:11:29 +0100
In-Reply-To: <d122cbe2-3ea4-71cb-b4fb-9f90c7aef7d6@cs.tcd.ie>
Cc: Eric Rescorla <ekr@rtfm.com>, Andrew Sullivan <ajs@anvilwalrusden.com>, DoH WG <doh@ietf.org>, Martin Thomson <mt@lowentropy.net>
To: Stephen Farrell <stephen.farrell@cs.tcd.ie>
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Subject: Re: [Doh] panel discussion on DoH/DoC
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> On 11 Feb 2019, at 12:40, Stephen Farrell <stephen.farrell@cs.tcd.ie> wrote:
> 
> Signed PGP part
> 
> Hiya,
> 
> On 11/02/2019 00:16, Eric Rescorla wrote:
>> The general idea would be to have a list of DoH servers (operators, not
>> machines) and then to randomly select one for each client. We haven't
>> decided to do this, so also haven't decided on how we'd implement it :)
> 
> I agree that picking one like that is no worse and likely better than
> round robin or similar, when considering how the DoH servers can affect
> the browser user's privacy in "normal" scenarios.

If you pick more than one and your information then subsequently leaks, how do you establish who leaked it?  One could keep a log, but then one has to protect the log.  One could devise some interesting hash-based selection algorithm, but the inputs would have to remain stable and the algorithm somehow accessible.

Sounds messy.

Eliot