RFC 4408 · EXPERIMENTAL · 2006

Sender Policy Framework for Authorizing Use of Domains in E-Mail, Version 1

Overview

RFC 4408, “Sender Policy Framework for Authorizing Use of Domains in E-Mail, Version 1”, is an Experimental document published in April 2006 by M. Wong, W. Schlitt. It has since been updated by RFC 6652. It has been obsoleted by RFC 7208 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

E-mail on the Internet can be forged in a number of ways. In particular, existing protocols place no restriction on what a sending host can use as the reverse-path of a message or the domain given on the SMTP HELO/EHLO commands. This document describes version 1 of the ender Policy Framework (SPF) protocol, whereby a domain may explicitly authorize the hosts that are allowed to use its domain name, and a receiving host may check such authorization. This memo defines an Experimental Protocol for the Internet community.

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

What “Experimental” means

Describes a specification that is part of a research or development effort, published so the community can gain experience with it.

Read this RFC

The canonical text of RFC 4408 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Obsoleted by
RFC 7208
Updated by
RFC 6652
Other RFCs from 2006

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