RFC 2234 · PROPOSED STANDARD · 1997

Augmented BNF for Syntax Specifications: ABNF

Overview

RFC 2234, “Augmented BNF for Syntax Specifications: ABNF”, is a Proposed Standard document published in November 1997 by D. Crocker, P. Overell. It has been obsoleted by RFC 4234 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

In the early days of the Arpanet, each specification contained its own definition of ABNF. This included the email specifications, RFC733 and then RFC822 which have come to be the common citations for defining ABNF. The current document separates out that definition, to permit selective reference. Predictably, it also provides some modifications and enhancements. [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 2234 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Obsoleted by
RFC 4234
Other RFCs from 1997

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