SPF, DKIM, and DMARC

The Old Horse named SMTP

Email is old. The first message sent across a computer network was sent in 1971. The current email protocol, SMTP, was codified under RFC 788 in 1981 and while it has been updated over the past 42 years (Man, I’m old), the core functionality in SMTP hasn’t changed much at all.…

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How Does SPF Work?

No, I’m not talking about sunscreen. The SPF I’ll be discussing here is Sender Policy Framework. It’s an email security measure that can prevent unauthorized use of your email domain name. I’ll be going over a few things in this post, but if you just want to know how to craft an SPF record, you can scroll to the “The SPF Puzzle” section below.…

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