Am 13. August 2019 um 05:42 Uhr -0700 schrieb Mark Sapiro:
The question is not whether they support ARC, but whether they will trust you.
Well. That's nothing new, given that GMail and Microsoft liberally reject e-mail from small providers for no reason anyway (I have experienced it myself). If this situation doesn't change with ARC, I can live with this (by paying for an SMTP relay provider that proxies my e-mail).
However, I thought the entire point in ARC was fixing automatic rejections caused by DMARC invalidation by mailing lists, which are vital for so many open-source projects (including Mailman iself). If ARC falls short of solving that problem, because the large providers do not automatically trust ARC, then supporting ARC on my mailing list server is kind of void. Why should almighty Microsoft trust my small personal mailing list server?
ARC can only achieve its goal with black-listing untrusted relays rather than white-listing known good ones, because it is simply unfeasable to manually maintain a list of all open-source project mailing lists in the entire world. I could set a new one up tomorrow, how should you know?
-- Blog: https://mg.guelker.eu