Understand different email protocols for secure and efficient communication.
Email Protocols
RFC 3464: An Extensible Message Format for Delivery Status Notifications
Defines the machine-readable DSN format used in bounce messages and delivery receipts.
RFC 6522: The Multipart/Report Media Type
Defines the multipart/report MIME type used to structure delivery status notifications and other administrative messages.
RFC 2142: Mailbox Names for Common Services, Roles and Functions
Defines standard role mailboxes every domain should maintain: postmaster@, abuse@, hostmaster@, etc.
RFC 5598: Internet Mail Architecture
Conceptual overview of the entire internet mail system: MSA, MTA, MDA, MUA roles and their interactions.
RFC 2392: Content-ID and Message-ID Uniform Resource Locators
Defines cid: and mid: URI schemes for referencing MIME parts within a message, used in HTML emails with embedded images.
RFC 1939: Post Office Protocol Version 3 (POP3)
Defines the POP3 protocol for downloading email from a server to a local client.
RFC 2177: IMAP4 IDLE Command
Defines the IDLE extension that lets an IMAP client be notified of new mail in real time without polling.
RFC 8058: Signaling One-Click Functionality for List Email Headers
Defines the List-Unsubscribe-Post header enabling one-click unsubscribe, required by Google and Yahoo bulk sender rules since Feb 2024.
RFC 2369: The Use of URLs as Meta-Syntax for Core Mail List Commands
Defines List-Unsubscribe, List-Help, List-Post and other headers for automating mailing list management.
RFC 6530: Overview and Framework for Internationalized Email
Framework RFC for EAI (Email Address Internationalization) supporting Unicode email addresses and headers.
