RFC 2554 · PROPOSED STANDARD · 1999

SMTP Service Extension for Authentication

Overview

RFC 2554, “SMTP Service Extension for Authentication”, is a Proposed Standard document published in March 1999 by J. Myers. It has been obsoleted by RFC 4954 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

This document defines an SMTP service extension [ESMTP] whereby an SMTP client may indicate an authentication mechanism to the server, perform an authentication protocol exchange, and optionally negotiate a security layer for subsequent protocol interactions. [STANDARDS-TRACK]

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 2554 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Obsoleted by
RFC 4954
Other RFCs from 1999

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