Re: [Bimi] Interpreting SANs according to draft-fetch-validation-vmc-wchuang-05 (was: bimi Digest, Vol 20, Issue 1)

Taavi Eomäe <taavi@zone.ee> Fri, 02 February 2024 10:59 UTC

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From: Taavi Eomäe <taavi@zone.ee>
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Subject: Re: [Bimi] Interpreting SANs according to draft-fetch-validation-vmc-wchuang-05 (was: bimi Digest, Vol 20, Issue 1)
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Hi,

 > SANs certificate are used for multiple domains (example.com, 
example.net, .eu, etc.)
 > Basicaly per 1 domain and all subdomains you need inly regular VMC. - 
1 logo

As described, there's just one SAN for a subdomain "www.example.com", 
most BIMI implementations display the logo, but at least one doesn't.

The current RFC draft is difficult to interpret if that behavior is 
correct or not.

 > Of cource subdomains have to be DMARC compliant and with policy 
"reject" or "Quarantine"

The letter itself only uses the higher-level domain "example.com" and 
DKIM/DMARC fully align.



Best Regards,
Taavi Eomäe
Zone Media OÜ - https://zone.eu