Alexander Inzinger-Zrock via Mailman-Users writes: > I considered ARC to be obsolete (and to should-be-replaced-by DKIM > 2)?
Not a chance. Both "ARC Failed" [1] and "DKIM 2" [2] are expired drafts. Doesn't mean they won't get picked up in the future, but there's not momentum for them now. ARC remains somewhat useful and not terribly burdensome for an intermediary such as a mailing list to implement. "ARC Failed" trash-talks ARC, but DKIM 2 as described is not a replacement for ARC that is helpful to mailing lists. In fact, it's more problematic for mailing lists than DMARC itself. Many Mailman mailing lists will find it impossible to participate in DKIM 2 at all, as I understand the MUSTs in that draft. (1) There's no reason to suppose that mom-and-pop ESPs and ISPs sending posts to mailing lists will implement DKIM2 section 2.2 quickly if at all. (2) See 2.4.1. Many mailing lists also remove and discard "problematic" MIME parts, and transform top-level text/html to text/plain, but do not satisfy the conditions that make this less problematic for "security gateways". So such mailing lists are likely to have trouble with any recipients that bounce mail that cannot be restored to original signed content. This is *worse* than DMARC because the draft provides no way to recognize such sites, nor any way to remedy the mail except to pass through content that violates list policy. Steve Footnotes: [1] https://www.ietf.org/archive/id/draft-adams-arc-experiment-conclusion-00.html [2] https://datatracker.ietf.org/doc/html/draft-ietf-dkim-dkim2-motivation-02 -- GNU Mailman consultant (installation, migration, customization) Sirius Open Source https://www.siriusopensource.com/ Software systems consulting in Europe, North America, and Japan ------------------------------------------------------ Mailman-Users mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3/lists/mailman-users.python.org/ Mailman FAQ: http://wiki.list.org/x/AgA3 Security Policy: http://wiki.list.org/x/QIA9 Searchable Archives: https://www.mail-archive.com/[email protected]/ https://mail.python.org/archives/list/[email protected]/ Member address: [email protected]
