More on DKIM2: VERP, async bounces, signatures and hops

As you might have seen me mention on Linkedin this week, I'm still working to fully wrap my head around DKIM2, specifically thinking about a couple of different things: the impact on DMARC and the impact on ESP platforms. Let me tell you what I know and what I don't know.DKIM2: The BasicsAs I covered in my previous Valimail "Ask Al" video, and this Valimail blog post, the goals of DKIM2, generally speaking, are to address DKIM replay, prevent backscatter, and to find a way to deal with message changes that break authentication (like secure email gateways/SEGs rewriting links to inspect and track links clicked on by their users). All good stuff. I very much want to see backscatter die once and for all, and while DKIM2 probably won't really change life too much for email senders (i.e. the customers of email service providers and marketing automation platforms), it will have some potential for impact when it comes to those email service provider (email sending) and mailbox provider…