Beware the oversimplification


Setting up a DMARC record is the easy bit. Anyone can publish a record in DNS that will trigger reports to them. The challenge is what to do with those reports and now to manage them.
DMARC is a complex protocol. It builds on two other protocols, each with their own nuances and implementation issues. I’ve written in the past about what DMARC is, what you need to know to decide if you’re ready for DMARC and walking through whether or not you should publish DMARC. I’ve done talks where it’s taken me 20 minutes and dozens of slides to set up the context for explaining DMARC. Even experienced email folks can have moments where we get confused by some of the nuances.
DMARC is not a passive protocol. DMARC is an active protocol. Even with a p=none record, there is ongoing monitoring and work. Why consume reports if you’re not going to monitor them? The reports are there so that senders can monitor their authentication. If you’re not monitoring, then why waste cycles and bandwidth to receive them? Do you even know if your mail aligns? Can your mail server handle emails with attachments larger than 10MB? Does your mail server block .zip files? All of these things can cause your mail to be rejected and you won’t receive reports.
Postmark has a great post on DMARC and even has some examples of reports.
I know, I know, there’s a lot of fear mongering about how any company not publishing DMARC isn’t going to get to the inbox. We’re not there, yet. We likely won’t be there in the next few years. We may never get there. In any case, it’s much better to actually think about what you’re going to do with DMARC Plus, ISPs are already checking for DMARC style alignment even in the absence of a DMARC record. You don’t have to publish DMARC for this to happen, it already does.
I’ve said it before: publishing a DMARC record is a good idea. But every company needs to take minimal steps to figure out if publishing DMARC, even just to receive aggregate reports, is the right thing for them. It’s not right for every company or domain at the moment.

About the author

Add comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.

By laura

Recent Posts


Follow Us