PART 1 - SPF Record

Currently, the three protocols you need to put into place to secure and authorize your email are SPF, DMARC and DKIM.  This first post will talk about the easiest to implement, Sender Policy Framework (SPF).

To quote Wikipedia:

(See Sender Policy Framework: “Sender Policy Framework (SPF) is an email authentication method designed to detect forging sender addresses during the delivery of the email. SPF alone, though, is limited to detecting a forged sender claim in the envelope of the email, which is used when the mail gets bounced. Only in combination with DMARC can it be used to detect the forging of the visible sender in emails (email spoofing), a technique often used in phishing and email spam.

SPF allows the...