RFC 9422 · PROPOSED STANDARD · 2024

The LIMITS SMTP Service Extension

Overview

RFC 9422, “The LIMITS SMTP Service Extension”, is a Proposed Standard document published in February 2024 by N. Freed, J. Klensin. The canonical text is published by the RFC Editor.

Abstract

This document defines a LIMITS extension for the Simple Mail Transfer Protocol (SMTP), including submission, as well as the Local Mail Transfer Protocol (LMTP). It also defines an associated limit registry. The extension provides the means for an SMTP, submission, or LMTP server to inform the client of limits the server intends to apply to the protocol during the current session. The client is then able to adapt its behavior in order to conform to those limits.

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 9422 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

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