9.1. Normative References

The following are normative references essential to the RFC 8141 specification:

[RFC20] ASCII Format

Cerf, V., "ASCII format for network interchange", STD 80, RFC 20, DOI 10.17487/RFC0020, October 1969.

Defines the ASCII character format for network exchange, which is the foundation for the URN character set.

[RFC2119] Key Words

Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997.

Defines the meaning of keywords (such as MUST, SHOULD, MAY) used in RFCs to indicate requirement levels.

[RFC3986] URI Generic Syntax

Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, DOI 10.17487/RFC3986, January 2005.

Defines the generic syntax for Uniform Resource Identifiers (URIs); URNs are a subset of URIs.

[RFC5226] IANA Considerations Guidelines

Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, DOI 10.17487/RFC5226, May 2008.

Provides guidelines for writing IANA Considerations sections in RFCs.

[RFC5234] ABNF Syntax Specification

Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, DOI 10.17487/RFC5234, January 2008.

Defines Augmented Backus-Naur Form (ABNF) for syntax specifications; RFC 8141 uses ABNF to define URN syntax.