Re: [dmarc-ietf] ARC-Seal is meaningless security theatre

Bron Gondwana <brong@fastmailteam.com> Mon, 07 August 2017 23:15 UTC

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From: Bron Gondwana <brong@fastmailteam.com>
To: dmarc@ietf.org
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Date: Tue, 08 Aug 2017 09:15:03 +1000
Archived-At: <https://mailarchive.ietf.org/arch/msg/dmarc/K6Vw5MTd5_tTiPje1DEw2IX_aC4>
Subject: Re: [dmarc-ietf] ARC-Seal is meaningless security theatre
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On Tue, 8 Aug 2017, at 00:50, Tim Draegen wrote:
>> On Aug 7, 2017, at 1:21 AM, Bron Gondwana
>> <brong@fastmailteam.com> wrote:>> 
>> A more cheap and nasty fix, assuming it's too late/complex to change
>> the protocol more, would be to keep AS, but change the validation to
>> only require checking the most recent AS, since validating the rest
>> is meaningless.> 
> Bron, thanks for sharing your insight. I don't think it's too
> late/complex to incorporate direct real world experience into the
> specification.> 
> I tried to express my own attitude in the Prague meeting: the email
> space is special because it is huge. It doesn't make sense to pretend
> that it isn't. Instead, let's build tech to solve real problems, test
> it against the install base, and make the tech better based on what is
> learned.> 
> AFAICT, ARC is at the very beginning of the "test it against the
> install base" phase.
Thanks Tim,

We'll set ARC up at FastMail and experiment with it for sure.  The code
is pretty much ready to slot into place, and while nobody is filtering
on it, it's easy enough to play with.
It's not like ARC is worse than nothing (apart from maybe the increased
DNS load).  Regardless of our opinion of how good it is, we'll certainly
implement anything which helps our users' mail be delivered!  But it
would be nice to help make it even better if we get a chance to
influence the technology choices :)
Bron.


--
  Bron Gondwana, CEO, FastMail Pty Ltd
  brong@fastmailteam.com