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Re: [dmarc-ietf] finer grained org domain

Dave Crocker <dhc@dcrocker.net> Tue, 18 August 2020 16:48 UTC

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To: Tim Wicinski <tjw.ietf@gmail.com>
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From: Dave Crocker <dhc@dcrocker.net>
Organization: Brandenburg InternetWorking
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Date: Tue, 18 Aug 2020 09:48:45 -0700
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Subject: Re: [dmarc-ietf] finer grained org domain
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On 8/18/2020 9:43 AM, Tim Wicinski wrote:
> I do think the tree walk deserves another look.   Years back when it 
> was brought up,
> there was lots of talk of overloading resolvers. But as someone who 
> spent the past
> several years looking at the DNS query data of good sized SaaS 
> domains, DMARC lookups
> (or even DMARC NXDOMAINs) were on the low end of the spectrum.  
> Nowadays, all web
> properties point to CDNs, et al with 30 second TTLs.

To be entirely obvious:

badactor.a.b.c.d.e.f.g.h.i.j.k.l.m.n.o.p.yougetheidea.example.com

produces a possible denial of service attack.  hence, no tree-walking.

d/

-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net

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