2023/06/05

SPF (Sender Policy Framework) records are DNS TXT records like v=spf1 _include=${email_server_domain} ~all. SPF records help email servers verify that another email server is allowed to send messages from a domain (e.g. foo@domain.com should only be sent by servers listed in an SPF record on a DNS server with authority over domain.com). More info at https://www.cloudflare.com/learning/dns/dns-records/dns-spf-record/

DKIM is another TXT record that issues public keys to check signature headers in email: https://www.cloudflare.com/learning/dns/dns-records/dns-dkim-record/