>> [RFC6377] provides some guidance on using DKIM with Mailing lists. >> The following mitigation techniques can be used to ease >> interoperability issues with DMARC and Mailing lists: > >It should probably be indicated whether these techniques would be applied >to all messages, or only to messages sent from domains with a DMARC >policy other than "p=none". (I prefer the latter.) It's an implementation issue, depending on whether the list software can get the DMARC policy from a DNS query or from an Authorization-Results header. My MTA puts an A-R header on incoming mail so I have a shim after the list manager that looks at the A-R header and rewrites the From: address (into dmarc.fail addresses, which some people imagine are not deliverable) if it sees a DMARC policy. >> o Configuring the MLM to "wrap" the message in a MIME message/rfc822 >> part and to send as the Mailing List email address. Many email >> clients (as of the publication of this document), especially >> mobile clients, have difficulty reading such messages and this is >> not expected to change soon. > >This seems like a quite elegant solution. I'm very surprised by the second >sentence - are these clients that have difficulty with many Content-Types >or is it a specific issue for message/rfc822? It's a one-entry MIME digest, so it looks like a digest, not an individual message. R's, John