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RFC 5234 - Augmented BNF for Syntax Specifications: ABNF

  • Status: Internet Standard
  • Published: January 2008
  • Stream: IETF
  • Obsoletes: RFC 4234
  • Errata: No Errata

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.

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. The differences between standard BNF and ABNF involve naming rules, repetition, alternatives, order- independence, and value ranges. This specification also supplies additional rule definitions and encoding for a core lexical analyzer of the type common to several Internet specifications.

Table of Contents​

Authors' Addresses​

Dave Crocker (editor) Brandenburg InternetWorking 675 Spruce Dr. Sunnyvale, CA 94086 US

Phone: +1.408.246.8253 EMail: [email protected]

Paul Overell THUS plc. 1/2 Berkeley Square, 99 Berkeley Street Glasgow G3 7HR UK

EMail: [email protected]

Copyright (C) The IETF Trust (2008).

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