Canonical URL:
https://www.rfc-editor.org/bcp/bcp14.txt

Cite this BCP: TXT

BCP 14 contains the following RFCs:
NumberFilesTitleAuthorsDateMore InfoStatus
RFC 2119, BCP 14ASCII, PDFKey words for use in RFCs to Indicate Requirement Levels S. BradnerMarch 1997Updated by RFC 8174, ErrataBest Current Practice
RFC 8174, BCP 14ASCII, PDFAmbiguity of Uppercase vs Lowercase in RFC 2119 Key WordsB. LeibaMay 2017Updates RFC 2119, ErrataBest Current Practice

Abstract of RFC 2119

In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.

Abstract of RFC 8174

RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings.


For the definition of Status, see RFC 2026.

For the definition of Stream, see RFC 4844.


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