Thank you for your reply and the link. That's very helpful and I agree this looks like the explanantion. Do you know of a definitive list anywhere that shows t

Thank you for your reply and the link. That's very helpful and I agree this looks like the explanantion. Do you know of a definitive list anywhere that shows the different uses made of DNS TXT records? I know Google and plenty of others use them for domain verification but I'm more interested in protocols like SPF, DKIM and DMARC but I've been unable to find a list. (edit: added missing word)