Uniform Resource Name (URN) Namespace Registration Transition
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Extracted elements (12)
RFC 8141 adopted a new model focusing on encouraging registration of all namespaces that follow the formal namespace syntax, collecting as much information as possible, rather than requiring IETF Consensus. This shift was intended to reduce barriers and improve consistency of namespace identification.
The predecessor registration procedure (RFC 3406) required IETF Consensus for formal URN namespaces. This requirement discouraged registrations and increased the risk of 'squatting'—use of names without registration—leading to potential confusion when the same name identifies different namespaces with different rules.
URN registration practices within the ISBN and ISSN namespaces are expected to evolve with their respective ISO standards without requiring resubmission of templates or formal IETF/IANA approval. This avoids the overhead of formal re-registration each time the underlying ISO standard is revised.
IANA must be prepared to maintain a URN Namespaces registry whose contents reflect old-style templates for some namespaces and newer RFC 8141-compliant ones for others, since this document and RFC 8141 do not supersede existing registrations except those for ISBN and ISSN.
RFC 3188 specifying the NBN URN namespace remains in effect and was not reclassified as Historic by this document; when RFC 3188 is revised, it should be accompanied by a new registration template conforming to RFC 8141.
For URN namespaces other than ISBN and ISSN, reregistration with new RFC 8141-compliant templates is recommended but not required. Until updated, existing registration templates should be read as not requiring or allowing any features not permitted by the earlier URN (RFC 2141) and registration (RFC 3406) specifications.
The portions of the ISBN and ISSN registry entries that point to ISO standards are intended to identify current versions of those standards (which may change over time), rather than only the versions active at the time this document was approved.
The NBN (National Bibliography Number) URN namespace is an umbrella concept covering identifier systems used by national libraries for resources lacking other identifiers. URN:NBN syntax guarantees global uniqueness by requiring country codes and institutional identifiers within the Namespace Specific String (NSS), e.g., urn:nbn:fi-fe19981001.
The revised ISBN URN namespace (superseding RFC 3187) supports both the legacy ten-character ISBN-10 identifiers (ISO 2108:1992) and the thirteen-character ISBN-13 identifiers introduced in ISO 2108:2005, reflecting ISO 2108:2017.
The updated ISSN URN namespace (superseding RFC 3044) incorporates the linking ISSN (ISSN-L), introduced in ISO 3297:2007, which designates a single ISSN for all media of a serial publication regardless of how many media forms exist, whereas traditional ISSN applies to a single medium only.
IANA maintains the Uniform Resource Names (URN) Namespaces registry. This document directs IANA to update the ISBN and ISSN namespace entries to reflect new RFC 8141-compliant templates, and instructs IANA to maintain a registry whose contents may reflect both old-style and new-style templates simultaneously.
This specification merely transitions a set of URN namespace registrations and does not itself introduce security implications. Security implications associated with particular namespaces are expected to be documented in their individual registration templates as specified in RFC 8141.