title: Internet Protocols Handbook: The Most Complete Reference for Developing Internet Applications
author:  Dave Roberts 
description: Dave Roberts (Fremont, CA) is an expert on communications software development, and the author of The Coriolis Group's Developing for the Internet with Winsock and PC Game Programming EXplorer. He is currently marketing manager with ZeitNet, Inc./Cabletron Systems, a developer of high-speed networking technology.
zlib_text: Network Working Group
  D. Crocker, Editor
  Request for Comments: 4234
  Brandenburg InternetWorking
  Obsoletes: 2234
  P. Overell
  Category: Standards Track
  THUS plc.
  October 2005
  Augmented BNF for Syntax Specifications: ABNF
  Status of this Memo
  This document specifies an Internet standards track protocol for the Internet community, and requests
  discussion and suggestions for improvements. Please refer to the current edition of the “Internet Official
  Protocol Standards” (STD 1) for the standardization state and status of this protocol. Distribution of this memo
  is unlimited.
  Copyright Notice
  Copyright © The Internet Society (2005). All Rights Reserved.
  Abstract
  Internet technical specifications often need to define a formal syntax. Over the years, a modified version
  of Backus-Naur Form (BNF), called Augmented BNF (ABNF), has been popular among many Internet
  specifications. The current specification documents ABNF. It balances compactness and simplicity, with
  reasonable representational power. 