Spam Resource: DELIVTERMS: Sender Policy Framework (SPF)

Al Iverson just posted another insightful article on Spam Resource:

Sender Policy Framework (SPF) is one of two primary types of email authentication mechanisms used by email senders today (the other being DKIM). SPF is a “simpler” protocol than DKIM, in that SPF is based around a text record for your domain name that contains the IP addresses of the mail servers that are allowed to send mail on your behalf.You can lookup the SPF record for Spam Resource here, using my XNND DNS Tools website. As of this writing, that SPF record looks like this:ip4:213.138.100.131 ip6:2607:f2f8:a760::2 ip4:206.125.175.2 include:_spf.google.com -allIt contains two regular IPv4 IP addresses, one IPv6 IP address, and an “include” mechanism that references Google’s SPF record. Decoding this tells us that I want those three servers (with those three IP addresses) to be able to send mail using my domain name spamresource.com, and the “include” for Google is because I am a user of GSuite/Google for Business

Read more here: DELIVTERMS: Sender Policy Framework (SPF)