https://nalar.dev/tags/dkim/ Recent content in DKIM on Nalar Hugo en-us Sat, 19 Sep 2026 00:00:00 +0000 https://nalar.dev/smtp-sender-identity-from-spf-dkim-dmarc/ Sat, 19 Sep 2026 00:00:00 +0000 https://nalar.dev/smtp-sender-identity-from-spf-dkim-dmarc/ <p>SMTP answers a transport question: which server accepts this message and relays it toward its destination? It does not, by itself, prove that the address displayed in the message&rsquo;s <code>From:</code> header belongs to the system that opened the SMTP connection.</p> <p>That distinction explains a common surprise. A mail client can connect to an external SMTP service, authenticate successfully, and submit a syntactically valid message with <code>From: user@gmail.com</code>. The SMTP login proves that the client may use that service. It does not give the service authority over <code>gmail.com</code>.</p>