Blog
How email works, and how it is secured.
Plain explanations, written by the people who build the scanner. Every claim is sourced, usually to the RFC it comes from.
DMARC at p=none: what it does, and what it doesn't
p=none gets you reports, not protection. The common ways unmanaged DMARC fails, and how to tell when a stricter policy is safe for your domain.
8 min read- Identity
Email security, RFC by RFC: from SMTP to DMARCbis
Each email standard, its year and its status, from RFC 821 to RFC 9989. Which are standards, which were experiments, and what replaced what.
9 min read- Identity
- Transport
- Delivery
A history of email, sourced: 1971 to DMARCbis
From Tomlinson's 1971 ARPANET message to the 2026 DMARC standards. Every date checked against the RFC or the record it comes from.
7 min readHow email is delivered: MX, SMTP and every hop
From submission to mailbox: how servers find each other through MX records, hand off over SMTP, and what each receiver checks along the way.
7 min read- Delivery
- Transport
What is email? The message, the envelope, and the record
An email is two things: an envelope servers read and a message people read. What each part is, and why the From line on its own proves nothing.
6 min read- Identity