Re: [dmarc-ietf] WGLC review of draft-ietf-dmarc-dmarcbis-30

[Jim Fenton <[e-mail]>]

On 30 Mar 2024, at 17:22, John R. Levine wrote:

>>>> Entities other than domains: Public suffixes aren’t (necessarily) domains,
>>>
>>> Of course they're domains.  What else could they be?  The things that are out of scope are IP addresses, ASNs, magic tokens in the messages, stuff like that.
>>
>> I’m probably being pedantic here: is “gov” a domain?
>
> Let's check:
>
> $ dig gov soa
>
>  ; <<>> DiG 9.10.6 <<>> gov soa
>  ;; global options: +cmd
>  ;; Got answer:
>  ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 63612
>  ;; flags: qr rd ra ad; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
>
>  ;; OPT PSEUDOSECTION:
>  ; EDNS: version: 0, flags:; udp: 1232
>  ;; QUESTION SECTION:
>  ;gov.				IN	SOA
>
>  ;; ANSWER SECTION:
>  gov.			300	IN	SOA	a.ns.gov. dns.cloudflare.com. 1711843800 3600 900 604800 300
>
> Yup, it's a domain.

I stand corrected on that.

>> Mine wasn’t a good example. There are a few public suffixes that have more than 5 labels. Presumably that means there are registered domains that are 6 levels down, and my reading of the tree walk is that a policy published there would never be seen. But who knows if they’re actually sending email.
>
> There aren't any in the PSL.  That's where the limit of 5 came from. We've had people say there are deeper ones; if there are it wouldn't be hard to bump up the limit from 5 to whatever.

Might be worth bumping up. Examples:

execute-api.cn-north-1.amazonaws.com.cn
cn-northwest-1.eb.amazonaws.com.cn

(Amazon seems to have most of the really long ones)

-Jim