Re: [dmarc-ietf] Genart last call review of draft-ietf-dmarc-psd-08

Alessandro Vesely <> Tue, 14 April 2020 09:55 UTC

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From: Alessandro Vesely <>
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Date: Tue, 14 Apr 2020 11:55:12 +0200
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Subject: Re: [dmarc-ietf] Genart last call review of draft-ietf-dmarc-psd-08
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On Fri 10/Apr/2020 15:38:40 +0200 Todd Herr wrote:
> On Thu, Apr 9, 2020 at 7:09 PM John Levine <> wrote:
>> In article <> you write:
>>>   1. "" is not a TLD. TLDs are single label domains - there are
>>>   ccTLDs and gTLDs.
>> Right.
> I don't disagree, but what I was going for here was some level of
> consistency with section 3.2 of RFC 7489, which reads in part:
>    1.  Acquire a "public suffix" list, i.e., a list of DNS domain names
>        reserved for registrations.  Some country Top-Level Domains
>        (TLDs) make specific registration requirements, e.g., the United
>        Kingdom places company registrations under "";

That text says TLD .uk made decision so and so.  It doesn't imply that
is somehow to be considered a TLD.

That wikipedia page is questionable.

> The point of the paragraph in question wasn't to define TLDs (or PSDs) but
> rather to better define "domain names reserved for registration".


>>> 2. The invocation of the PSL compounds the issue that was raised by
>>> Dave Crocker. How DMARC (RFC 7489) determines the organizational domain
>>> is orthogonal to this proposal which simply calls for a conditional
>>> additional check at the "org - 1" level. I recommend striking the
>>> penultimate paragraph in the proposal.>>
>> I'd suggest weasel wording it to say that the domain above an org
>> domain is often known as a public suffix domain, which typically
>> delegates the org domains below it to a unrelated parties.  This spec
>> allows public suffix domains to publish policies to supplant those of
>> their child org domains ...


>> I agree we should stay as far from mentioning the PSL and its specific
>> implementation as possible.  Who knows, someday people might get
>> around to trying my dbound in DNS implementation instead.

Nevertheless, the concept of *Public Suffix* is independent of its only known
implementation (and of some acceptations of the term "public").  It is the
concept that 7489bis is going to craft.  I propose to stick to the term Public
Suffix, whatever its future definition is going to be.