Registers the application/mbox MIME type for the traditional Unix mbox mailbox format.

Extends IMAP URLFETCH to support binary and format-converted part retrieval.

Overview article covering all five MIME RFCs as a suite: format, media types, header extensions, registration, and conformance.

Reference catalog of 47 DNS-based email blocklists. Each entry covers what the list targets, how it affects SMTP delivery, and how to request removal.

Composite zone combining SBL (spam sources), XBL (exploited IPs), and PBL (policy block list) into a single DNSBL query. The most widely deployed IP blocklist ...

Defines port 587 as the mail submission port, separating client-to-server submission from MTA-to-MTA relay on port 25.

Earlier version of the submission RFC. Obsoleted by RFC 6409.

Defines the machine-readable DSN format used in bounce messages and delivery receipts.

Defines the multipart/report MIME type used to structure delivery status notifications and other administrative messages.

Defines the ARF (Abuse Reporting Format) used in Feedback Loop (FBL) complaint reports from mailbox providers.