RFC 2033: Local Mail Transfer Protocol

SMTP [SMTP] [HOST-REQ] and its service extensions [ESMTP] provide a mechanism for transferring mail reliably and efficiently. The design of the SMTP protocol…

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Outgoing relationships (7 related RFCs)

Informative reference — RFC 2034: SMTP Service Extension for Returning Enhanced Error Codes
Informative reference — RFC 1894: An Extensible Message Format for Delivery Status Notifications
Informative reference — RFC 1869: SMTP Service Extensions
Informative reference — RFC 1652: SMTP Service Extension for 8bit-MIMEtransport
Informative reference — RFC 1830: SMTP Service Extensions for Transmission of Large and Binary MIME Messages
Informative reference — RFC 1047: Duplicate messages and SMTP
Informative reference — RFC 1854: SMTP Service Extension for Command Pipelining

Incoming relationships (11 related RFCs)

Normatively referenced by — RFC 5429: Sieve Email Filtering: Reject and Extended Reject Extensions
Normatively referenced by — RFC 3848: ESMTP and LMTP Transmission Types Registration
Normatively referenced by — RFC 6710: Simple Mail Transfer Protocol Extension for Message Transfer Priorities
Informatively referenced by — RFC 5598: Internet Mail Architecture
Informatively referenced by — RFC 6531: SMTP Extension for Internationalized Email
Informatively referenced by — RFC 5336: SMTP Extension for Internationalized Email Addresses
Informatively referenced by — RFC 3886: An Extensible Message Format for Message Tracking Responses
Informatively referenced by — RFC 8689: SMTP Require TLS Option
Informatively referenced by — RFC 4496: Open Pluggable Edge Services (OPES) SMTP Use Cases
Informatively referenced by — RFC 9208: IMAP QUOTA Extension
Informatively referenced by — RFC 9422: The LIMITS SMTP Service Extension